Say your birth certificate was wrong- its your birthday today...
Or start ripping the house up...
Or best of all... Stomp around the hose, banging things, look at her with evil looks and when she asks 'what's up dear?' snap back 'nothing. why wold anything ever be wrong'... It works for them and they always get their own way.
Or maybe, hide her jewellery and shoes and say you will ransom them back...
Stu