Kevin Mazur, WireImage
Now, US Weekly is reporting that Marc is gearing up for a massive custody battle ... but his motives might not have just the twins in mind. "[Marc] hit the roof" when he saw photos of Jennifer and Casper on the beach in Hawaii with the twins, one source tells the magazine. "It caused a huge blowup" between Lopez and the jealous Anthony.
Despite the fact that J.Lo and Marc had previously decided on the custody situation of the twins -- with primary custody going to Lopez -- Anthony is now having a change of heart. "[He's] going back on his word and saying his wants joint custody," claims the insider.
"[Marc] wants to make Jennifer suffer," continues the source. "Because she's having fun with someone new, and he knows this will hurt her on the deepest level."
But if Anthony wants a fight, Lopez is ready for it. Like any protective mama, J.Lo is worried how the custody battle could effect the twins negatively. "[She's] ready to smash him if he tries anything," a friend of Lopez's tells US. "It's getting vicious."
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