If she is not spending and one day, she spend 32k then that's not a big deal. Just tell her, that she should manage it within the budget and the money you send her. Use card on joint account only in emergencies as amount borrowed from card has to be paid back as otherwise its defaulted and fined.
if she has gathered the money from budget you have allotted her then dont bother as its her money and she must have saved it for something big which makes her happy.