We have the family plan for spouse and myself. I want the children to start using a password manager but don't want them to have access to all the parent's passwords.
Is it possible to have one vault for them and one for parents but the children have no access to the parent's passwords?
Building onto Tom's recommendation, you could have your child's permissions as read only to begin with. This would allow them to access and use their passwords and other items without accidentally editing them. (This could cause them to lose a OTP for example). Once they're familiar with the workings of 1Password, you can add the read/write permission back in.
Standard used in my previous deployments was for families with (smaller) kids only having very few passwords in the default shared family vault (but left it in for future use) and just create new vaults 'per child' in which the parents would participate. E.g.
