Make a Family Time Capsule to Open Years From Now

I want to create a family time capsule that we'll open in [number of years] years. Help me plan this properly so it feels meaningful and actually lasts.

About us right now:
- Who's in the family: [list each person's name and age, plus any pets]
- What's going on in our lives at the moment: [a couple of sentences — a new baby, a house move, a child starting school, a tough year we got through, or just an ordinary chapter we want to remember]
- When we plan to open it: [e.g. our youngest's 18th birthday, our 25th wedding anniversary, in exactly 10 years]
- Where we'll store it: [e.g. loft, under a bed, with a relative for safekeeping]
- Rough budget if we need to buy anything: [e.g. nothing, £20, £50, or 'just things we already have']

Please give me:

1. A list of ideas for what to put inside, grouped into:
- Personal contributions from each family member (letters, drawings, lists of favourites)
- Snapshots of right now (a newspaper from today, a supermarket receipt, current prices, a printed photo, a Spotify playlist on paper)
- Things future-us will find funny, touching, or surprising
- Anything to avoid (items that won't survive, fads that will age badly)

2. A set of age-appropriate questions for each family member to answer in their own letter — the kind of prompts that lead to thoughtful, specific answers rather than generic ones.

3. A short letter from 'us today' to 'us in [number of years] years', around 200 words, written in a warm, honest, gently playful tone that I can adapt and personalise.

4. Practical advice on:
- The best type of container to use, and how to protect the contents from damp, light, and time
- A reliable way to make sure we actually remember to open it on the right date (calendar reminders, a sealed envelope handed to a relative, etc.)
- Whether to include any digital items, and how to make sure they'll still be readable years from now

Keep the tone warm and personal — not like a craft activity from a children's magazine. Use British spelling throughout.