Big things are about to start popping for the Olsen Twins.

The 22-year-old entertainment titans, who have been plagued by rumors of strife in recent months, have found something new to argue over–surgically expanding their bust lines!

Mary-Kate was left horrified, says a Star Magazine mole, after her sister Ashley suggested the former child stars purchase matching chest muscles.

“Ashley is considering getting her boobs done because she wants to look more voluptuous,” one Star snitch giggles, “and she told Mary-Kate that she wanted her to get one at the same time so that it wouldn’t be glaringly obvious that Ashley had work done.”

“That way, they could say that they had just both matured and were filling out naturally.”

Sorry Ash, it doesn’t sound like MK is in a Nip/Tuck kind of mood.

“She told Ashley no way! Mary-Kate hates being told what to do and how to look by Ashley. It drives her nuts. Anyway, she’s into that flat look and thinks clothes look better with less cleavage, so she’d rather be smaller and more stylish.”