[globular-toast]

It really depends what your arrangement is. Is everything shared between you? Then you need to track all accounts. You should look into automating ingest of your accounts data. Most banks/credit cards etc. should allow some kind of statement export. If not, consider switching provider.

I would advise not to worry about petty cash. Don't get pedantic. Worry about the big things. Just make a cash account for petty cash.

If you don't share accounts then just track your stuff and set up reimbursement account(s) for your family. You'll only know the net amount you need to transfer between yourselves to square up at the end of the month or whatever you agree to do.