No per-seat anything
Everyone gets their own account. Nobody pays for a seat.
Both parents, both grandmothers, the night nurse, the babysitter, the friends who only want the photos. Add as many as you like; the price does not move.
$1was $20once. Unlimited people, forever.
for the first 100 families — 99 left.

Nobody passes a login around
“multiple caretakers can use the same account”
In Milo everybody signs in as themselves, so every entry carries who logged it — and the timeline answers “was that you or me?” by itself. Four levels, and the line between them is drawn by the database rather than by hiding buttons.
Bring all of them
$1was $20for the first 100 families — 99 left.