{"h1":"Rett Syndrome vs Separation Anxiety Disorder in Young Children","faq":[{"a":"No. They are entirely separate things. Separation Anxiety Disorder is an emotional condition in an otherwise typically developing child, while Rett Syndrome is a genetic neurodevelopmental condition usually caused by a change in the MECP2 gene. One does not become the other.","q":"Can Separation Anxiety Disorder turn into Rett Syndrome?"},{"a":"Ask yourself one question: has my child lost skills she once had — hand use, babble, words — often with repetitive hand movements? That points toward Rett and needs a prompt review. If instead she is fully able but overwhelmed only when apart from you, and settles once reunited, that suggests separation anxiety. A clinician confirms either.","q":"How do I tell the difference at home?"},{"a":"Yes, very much so. Distress at being apart from a parent is a normal part of toddler development. It becomes a disorder only when it is intense, lasting and interferes with sleep, play, school or family life.","q":"Is some separation anxiety normal in young children?"},{"a":"Rett Syndrome is almost always linked to a change in the MECP2 gene, which sits on the X chromosome. It is most commonly recognised in girls. Any regression or loss of skills in a child should be reviewed promptly by a clinician.","q":"Why does Rett Syndrome mostly affect girls?"}],"lang":"en","slug":"what-is-the-difference-between-rett-syndrome-and-separation-anxiety-disorder-in-young-children","title":"Rett Syndrome vs Separation Anxiety Disorder in Young Children","entity":{"key":"rett","kind":"condition_vs_condition","name":"Rett Syndrome vs Separation Anxiety Disorder","slug":"rett-syndrome"},"lenses":[{"kind":"stakeholder","label":"Parent","value":"parent"},{"kind":"domain","label":"Context","value":"context"},{"kind":"intent","label":"Definition","value":"definition"},{"kind":"lifecycle","label":"Screen","value":"screen"},{"kind":"route","label":"Book-Assessment","value":"book-assessment"},{"kind":"empowerment","label":"Early Clarity","value":"early_clarity"}],"parent":null,"related":[{"lang":"en","slug":"what-is-the-difference-between-childhood-anxiety-and-rett-syndrome-in-young-children","title":"Childhood Anxiety vs Rett Syndrome in Young Children"},{"lang":"en","slug":"what-is-the-difference-between-developmental-regression-and-separation-anxiety-disorder-in-young-children","title":"Developmental Regression vs Separation Anxiety Disorder"},{"lang":"en","slug":"what-is-the-difference-between-self-regulation-difficulties-and-rett-syndrome-in-young-children","title":"Self-Regulation Difficulties vs Rett Syndrome"},{"lang":"en","slug":"what-is-the-difference-between-autism-spectrum-and-rett-syndrome-in-young-children","title":"Autism Spectrum vs Rett Syndrome in Young Children"},{"lang":"en","slug":"what-is-the-difference-between-developmental-trauma-and-rett-syndrome-in-young-children","title":"Developmental Trauma vs Rett Syndrome in Young Children"},{"lang":"en","slug":"what-is-the-difference-between-attachment-difficulties-and-rett-syndrome-in-young-children","title":"Attachment Difficulties vs Rett Syndrome in Young Children"}],"summary":"Rett Syndrome is a rare genetic neurodevelopmental condition, usually caused by an MECP2 change and seen mostly in girls, marked by a loss of acquired skills — purposeful hand use, babble, words — and repetitive hand movements after early typical development. Separation Anxiety Disorder is an emotional condition where a fully-able child becomes intensely distressed when apart from a carer, but keeps all her skills intact. Rett involves a biological loss of abilities; separation anxiety is a strong feeling about being apart with development preserved. The key question for parents: has my child lost skills (think Rett), or is my able child overwhelmed by being apart (think separation anxiety)?","answer_md":"*Two very different stories can look alike for a moment — one is woven into a child's genes, the other into a child's feelings — and telling them apart matters.*\n\n## In short\n**Rett Syndrome** is a rare genetic neurodevelopmental condition, almost always caused by a change in the *MECP2* gene and seen mostly in girls. After a period of typical early development, a child may slow down or lose skills she had — purposeful hand use, babble or words — and develop repetitive hand movements like wringing or wave-washing. **Separation Anxiety Disorder** is an emotional and behavioural condition: an otherwise typically developing child becomes intensely distressed when apart from a parent or carer, but keeps all her skills, hand use and abilities intact. In short — Rett involves a *loss* of acquired skills and is rooted in biology; separation anxiety is a *strong feeling* about being apart, with development fully preserved.\n\n## How they differ in everyday life\nWith **Rett Syndrome**, parents often notice a quiet *regression* somewhere between 6 and 18 months: a baby who was reaching, holding and babbling gradually stops, her hands begin to move in repetitive patterns, head growth may slow, and walking or coordination can change. It is present all the time — not only when a parent leaves the room — and it is a change in the child's underlying abilities, not her mood.\n\nWith **Separation Anxiety Disorder**, the child's skills are completely intact — she plays, speaks, uses her hands and learns normally. The distress shows up *around separation*: crying or clinging at drop-off, worry that something bad will happen to a parent, reluctance to sleep alone, or tummy aches before school. Crucially, once reassured or reunited, she settles and is herself again. A degree of separation upset is entirely normal in toddlers; it becomes a *disorder* only when it is intense, lasting and gets in the way of everyday life.\n\nThe simplest distinction for a parent: **Has my child lost skills she once had, with unusual hand movements (think Rett)? Or is my fully-able child overwhelmed by being apart from me (think separation anxiety)?**\n\n## When to seek help\nAny loss of skills a child previously had — hand use, babble, words, coordination — warrants a prompt developmental review, because regression is never something to wait out. Persistent, distressing separation worry that disrupts sleep, school or family life also deserves a gentle professional look. Either way, an early, unhurried assessment brings clarity and the right support.\n\n## The Pinnacle way\nThis is general information, not a diagnosis — a clinical [AbilityScore®](/ask/what-is-the-abilityscore-and-how-is-it-calculated) and any diagnosis are formed only at a Pinnacle Blooms Network centre, under qualified clinician care, never from an app or form. Our clinicians observe how your child moves, plays, communicates and copes, then shape the right path — [behavioural therapy](/behavioural-therapy) and family support where anxiety is the picture, and developmental, communication and motor support where regression is involved. Learn more about [Rett Syndrome](/rett-syndrome). Backed by 2.5 billion+ data points and 25 million+ therapy sessions across 70+ centres.\n\n## Trusted sources\nThe World Health Organization's ICD-11 frames Rett Syndrome among neurodevelopmental conditions and separation anxiety among the anxiety disorders; the American Academy of Pediatrics and HealthyChildren describe typical separation worry in young children and when it needs attention.\n\n**Next step —** Noticing lost skills, unusual hand movements, or distress that goes beyond ordinary clinginess? Book a developmental screening and let a clinician bring clarity.","canonical":"https://pinnacleblooms.org/ask/what-is-the-difference-between-rett-syndrome-and-separation-anxiety-disorder-in-young-children","editorial":{"reviewed_at":"2026-06-11T20:12:18.613642+00:00","reviewed_by":null,"developed_by":"SETU Consortium · Pinnacle Blooms Network"},"alternates":[{"href":"https://pinnacleblooms.org/ask/what-is-the-difference-between-rett-syndrome-and-separation-anxiety-disorder-in-young-children","lang":"en","indexable":true}],"dimensions":[],"meta_title":"Rett Syndrome vs Separation Anxiety in Children","meta_robots":"index, follow, max-image-preview:large","everyday_tip":"Keep a simple notebook of milestones. For separation worry, practise short, cheerful goodbyes with a clear 'I'll be back after lunch' and a small comfort object — but if your child seems to lose a skill she once had, note the date and book a review rather than waiting.","published_at":"2026-06-10T14:16:00.221239+00:00","reading_paths":[{"key":"understand","items":[{"lang":"en","slug":"what-is-the-difference-between-childhood-anxiety-and-rett-syndrome-in-young-children","title":"Childhood Anxiety vs Rett Syndrome in Young Children","reason":"Linked from this answer"},{"lang":"en","slug":"what-is-the-difference-between-attachment-difficulties-and-rett-syndrome-in-young-children","title":"Attachment Difficulties vs Rett Syndrome in Young Children","reason":"Linked from this answer"},{"lang":"en","slug":"what-is-the-difference-between-developmental-regression-and-separation-anxiety-disorder-in-young-children","title":"Developmental Regression vs Separation Anxiety Disorder","reason":"Linked from this answer"},{"lang":"en","slug":"what-is-the-difference-between-developmental-trauma-and-rett-syndrome-in-young-children","title":"Developmental Trauma vs Rett Syndrome in Young Children","reason":"Linked from this answer"},{"lang":"en","slug":"what-is-the-difference-between-self-regulation-difficulties-and-rett-syndrome-in-young-children","title":"Self-Regulation Difficulties vs Rett Syndrome","reason":"Linked from this answer"},{"lang":"en","slug":"what-is-the-difference-between-autism-spectrum-and-rett-syndrome-in-young-children","title":"Autism Spectrum vs Rett Syndrome in Young Children","reason":"Linked from this answer"},{"lang":"en","slug":"what-is-the-difference-between-rett-syndrome-and-childhood-sleep-difficulties-in-young-children","title":"Rett Syndrome vs Childhood Sleep Difficulties in Young Children","reason":"Same topic"},{"lang":"en","slug":"what-is-the-difference-between-rett-syndrome-and-persistent-toe-walking-in-young-children","title":"Rett Syndrome vs Persistent Toe-Walking","reason":"Same topic"},{"lang":"en","slug":"what-is-the-difference-between-rett-syndrome-and-school-readiness-gap-in-young-children","title":"Rett Syndrome vs School Readiness Gap in Young Children","reason":"Same topic"},{"lang":"en","slug":"what-is-the-difference-between-rett-syndrome-and-selective-mutism-in-young-children","title":"Rett Syndrome vs Selective Mutism in Young Children","reason":"Same topic"},{"lang":"en","slug":"what-is-the-difference-between-rett-syndrome-and-sensory-processing-differences-in-young-children","title":"Rett Syndrome vs Sensory Processing Differences in Young Children","reason":"Same topic"},{"lang":"en","slug":"what-is-the-difference-between-rett-syndrome-and-social-communication-difficulties-in-young-children","title":"Rett Syndrome vs Social Communication Difficulties in Young Children","reason":"Same topic"}],"label":"Understand the subject","total":17}],"what_to_watch":"Watch for a child who has lost skills she once had — purposeful hand use, babble or words — alongside repetitive hand movements like wringing or washing motions (this points toward Rett and needs a prompt review). Separation anxiety instead shows a fully-able child who is intensely distressed at being apart from a parent but settles once reunited.","authority_links":[{"url":"https://icd.who.int","code":null,"label":"WHO ICD-11: neurodevelopmental and anxiety disorders"},{"url":"https://www.healthychildren.org","label":"HealthyChildren (AAP): separation anxiety in young children"},{"url":"https://www.aap.org","label":"American Academy of Pediatrics: child development"}],"last_reviewed_at":"2026-06-10T14:16:00.221239+00:00","meta_description":"How Rett Syndrome and Separation Anxiety Disorder differ in young children — skill loss and hand movements vs distress at being apart. Warm, clear guidance","related_materials":[],"related_techniques":[]}