A source claims the two were seen riding in a car together near a resort in Big Sky, where the Pearl Harbor actor has a home.
"[Jennifer] spent several days with Ben out of town,” a source dished, adding the two “have a strong connection. It's all been quick and intense, but Jennifer is happy." The source noted that the exes were later spotted arriving back in L.A. on Saturday, May 8, via a private jet.
Then, OK! learned that Affleck was spotted multiple times secretly visiting the “If You Had My Love” singer at her house during the day. The actor was snapped being picked up in a white Escalade SUV, which apparently belongs to J.Lo, before being escorted to her mansion.
“So happy to share these kids with you. Luckiest parents in the world. Thanks for all the good you do,” he wrote alongside throwback photos of Garner and their children. “Happy Mother's Day.”
Meanwhile, Lopez shared a glimpse of her special celebration with photos of her fun-filled day with 13-year-old twins Emme and Max — whom she shares with ex-husband Marc Anthony — and her mother, Guadalupe Rodríguez.
"#MothersDay with my mommy and coconuts!" the "Let’s Get Loud" singer captioned the post.
In a separate post, Lopez paid tribute to her mom by sharing a touching video from her latest JLo Beauty campaign with her, Emme and Guadalupe. "It was my mom who instilled in us at a very young age that we could do anything. This was something that has really stayed with me," Lopez captioned the clip.
"Being a mom is my greatest joy, and today I think about my mommy and all the moms out there. This is your day," she added, "and I hope you are surrounded by love, gratitude and appreciation…enjoy it! #HappyMothersDay #IGotItFromMyMama #MamaGlowsBest."
PEOPLE was the first to report on Lopez and Affleck's Montana getaway.