Who would steal $100 in quarters?!?!?

$100 in quarters has been stolen from my electronic jug which shows clearly how much money is in there. There was actually $200 in it originally but after all my quarters disappeared I thought it best to hide the $100 bill somewhere much safer. It obviously had to have been done continuously over time. I've deduced the culprit of the $100 theft in quarters to two people in my household. My first suspect is the grandmother who has the daily opportunity to enter my dwelling in search for money to use at the bar and for gas money. Given the fact she hasn't been in my room for days she's less likely the thief than my brother. He has stolen before and lied on many accounts before. He has time before we leave for school every morning to enter my room and steal a dollar or two to feed his caffeine cravings. Since I haven't looked at my jug of quarters in a long while, its not hard to believe he stole them especially because he told me he was broke since March. He swore that he had not stolen them. He usually gets money from mowing my relative's lawn. My grandmother on the other hand has no job and receives no money except for those who happily give her money. So far I have no more suspicion of one than the other. What is your opinion?