J.Lo and Marc's Date Night

With their adorable 3-month old twins, Max and Emme, safe at home with a nanny, new parents Jennifer Lopez,38, and Marc Anthony,39, hit the Big Apple on April 27, where they spent a night out on the town at a pal's birthday party.

The happy couple arrived hand in hand at Sofrito Restaurant and posed for pictures with the birthday boy, New York Mets player Carlos Beltran.

"J.Lo was absolutely radiant," an onlooker tells OK!. "She said it was hard for her to leave the babies at home, but that becoming a mother is the best thing that's ever happened to her."