Brad Pitt
Brad Pitt celebrated his 55th birthday on Dec. 18. The actor is pictured speaking onstage during the 22nd Annual Hollywood Film Awards on Nov. 4, 2018 in Beverly Hills, California. Tommaso Boddi/Getty Images

Brad Pitt may have reached a custody agreement with Angelina Jolie, but that doesn’t mean he has a solid relationship with all six of their kids amid their divorce proceedings.

Pitt, who shares Maddox, 17, Pax, 15, Zahara, 13, Shiloh, 12, and twins Knox and Vivienne, 10 with Jolie, celebrated his 55th birthday on Dec. 18. Unfortunately, the “Once Upon a Time in Hollywood” star didn’t get to spend the day with all of his children.

A source told Us Weekly Pitt’s eldest son skipped out on his father’s birthday celebration, while the rest of his siblings spent the night at the actor’s home.

“Brad had the kids overnight — all but [eldest] Maddox — which was incredibly significant because it was the first time since the custody deal was recently reached,” the insider revealed.

However, Pitt reportedly realizes that while it will take time for everyone to adjust to the new arrangements, he “knows he is on the path to having the kids back in his life in a much more meaningful and significant way.”

Although Pitt is allowed to spend more time with his kids, it may take some time before he can actually be alone with them. “The visits will continue to be monitored, including the overnights until the therapists agree that it’s no longer needed,” the source explained.

“This is a transition time for the entire family, and it’s being done with a lot of input from the therapists.”

Pitt and Jolie reportedly reached their custody deal in November, however, the estranged couple has yet to finalize their divorce following their 2016 split.