Shared care log for adult siblings

The idea

When a parent starts needing real help, sibling coordination happens in a group text where the medication change from Tuesday is forty messages up, the out-of-state brother asks questions everyone has answered twice, and one sibling silently becomes the single point of failure holding it all in her head. Clinical caregiver platforms exist but they are built for agencies and care teams, not for four adult children with jobs.

The wedge is designing for the actual unit: a small family, mixed tech ability, unevenly distributed guilt. A shared timeline replaces the group text, an append-only med list with change history settles “who changed the dose” arguments, and a daily SMS digest keeps the sibling who will never install anything fully in the loop, including letting them post by simply replying to the text.

Who pays

The primary caregiver sibling, usually the one who lives closest, pays GBP 10 a month to stop being the family’s memory. This is the sandwich generation: peak earning years, acute pain, and a strong preference for anything that reduces both the load and the resentment. Distribution: caregiver Facebook groups and forums (r/AgingParents, AgingCare), eldercare bloggers and social workers who get asked for exactly this, and SEO on “shared caregiving app for siblings”.

MVP scope

• Family space with invites and magic-link auth
• Timeline posts with photos, mobile-first composer
• Med list with append-only change history and appointment calendar with assignments
• Weekly on-duty rotation schedule
• Daily SMS digest via Twilio, with reply-to-post webhook
• Skip for v1: provider/agency access, document vaults, health-device integrations, and HIPAA positioning (this is a family notebook, not a medical record)

Build KinLog, a web app for 3-5 adult siblings coordinating an ageing parent's care. Stack: Next.js (App Router), Supabase (Postgres + magic-link auth + storage), Twilio for SMS.

Core flow: one sibling creates a family space for the parent and invites the others by email or phone number. The space has four tabs: Timeline (posts with optional photos — "Mum ate well, BP 130/85, Dr Patel says reduce dose"), Meds (current list with dose and schedule, plus full change history showing who changed what and when), Calendar (appointments with an assigned sibling), and Rotation (a repeating weekly on-duty schedule).

Pages: family space with the four tabs, post composer (mobile-first, photo upload to Supabase storage), med editor, invite/settings screen, and a daily digest preview.

Implementation details: every evening at 7pm in the family's timezone, Twilio sends each member an SMS digest — new timeline posts, med changes, and tomorrow's appointments with who is on duty — because at least one sibling will never open the app, and the product fails if they fall out of the loop. Replying to the digest SMS posts the reply text to the timeline via a Twilio webhook, so the app-refusing sibling still participates. Med history is append-only; edits create new versions, never overwrite.

Pricing: GBP 10/month per family space, 30-day free trial, paid by whoever creates the space. No per-seat pricing.