Prepare a child for a big change before it happens

Help me prepare a child for a big change.

The change: [move, school, baby, job, other]
When it happens: [date or rough]
Child's age and temperament: [details]
What won't change: [anchors]
Worries I expect: [optional]

Ask me up to 3 short questions first if anything important is missing. Wait for my answers.

Then:
1. A timeline of what to say and when.
2. Practical prep steps (visits, books, routines).
3. Phrases for the hard feelings.
4. How to involve them without giving fake choices.

Only use what I've told you, leave blanks for anything I haven't given, and don't invent facts, diagnoses or legal outcomes. This is help with wording and planning, not legal, medical or counselling advice; point me to GOV.UK, Citizens Advice, NSPCC (0808 800 5000), Childline (0800 1111), Samaritans (116 123) or Refuge/National Domestic Abuse Helpline (0808 2000 247) where that fits, and call 999 if anyone is in immediate danger. UK English.

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