Jennifer Lopez Joins Marc Anthony by the Pool in Miami

He celebrated with close friends – and thousands of fans – Friday in Miami, and on Saturday, Marc Anthony had a quiet birthday celebration in Miami Beach with estranged wife Jennifer lopez and their 3-year-old twins, Max and Emme. 

"It looked like a fun family gathering at the pool," a source tells PEOPLE. "Everyone looked happy and festive." 

Anthony, who turned 43 on Friday, and Lopez were at entrepreneur friend Loren Ridinger's guesthouse, which is where the two often stayed before they acquired a condo at Miami's Viceroy Hotel complex.