Marc Anthony looking to change custody agreement with Jennifer Lopez

Deborah Kim

Marc Anthony (L) and his wife Jennifer Lopez pose at a news conference to announce "The Jennifer Lopez and Marc Anthony" collections in partnership with Kohl's Department Stores at The London West Hollywood hotel in West Hollywood, California, November 18, 2010. Kohl's will be the exclusive provider of the contemporary lifestyle brands in the U.S. and it will be available nationwide in Fall 2011 beginning with women's and men's apparel and accessories. REUTERS/Danny Moloshok (UNITED STATES - Tags: ENTERTAINMENT FASHION BUSINESS)

Marc Anthony and Jennifer Lopez may be amicable business partners, but trouble is stirring up in their personal lives.

Us Weekly reported the QViva! The Chosen co-creators are on the verge of a nasty custody battle due to Lopezs relationship with dancer beau Casper Smart.

According to the New York Daily News, Anthony is furious that his ex-wife has moved on and that she allows their children, three-year-old twins Emme and Max, to play with Smart.

A source told the website that the Rain Over Me singer hit the roof when he saw photos of his children with the 24-year-old on vacation in Hawaii.

It caused a huge blowup, the source said.

And while revenge may be sweet, its not pretty. Anthony reportedly wants to change his custody agreement with Lopez, who currently has primary custody, and pursue joint custody.

He wants to make Jennifer suffer because shes having fun with someone new, and he knows this will hurt her on the deepest level, the source said.

However, the Enough actress is ready for a big fight. Another source said she is ready to smash him if he tries anything... Its getting vicious, ano! ther sou rce said.

If being with a back-up dancer, whose probably looking for a sugar mama, means you might end up spending less time with your kids, you might want to reconsider your priorities.