Why Brad Pitt is 'not looking to leap into a serious relationship' right now (exclusive)

Brad Pitt is solely focusing on his family and work.

A source tells ET that the 54-year-old actor is “in a great place personally and professionally” as he heads back to the set of his upcoming movie, Once Upon a Time in Hollywood, after recently spending time with his six kids in London.

“He’s happy to be back in Los Angeles filming,” the source says. “He’s good-natured and professional on set. He is warm and authentic with everyone around. When he isn’t filming, he spends most of his time away in his trailer.”

The source notes that Pitt’s children with Angelina Jolie -- Maddox, Pax, Zahara, Shiloh, and the twins Knox and Vivienne -- have not visited their father during the film's production. In August, when Pitt was filming Ad Astra, a source told ET, “He's a movie star in the best way, prepared, on time and friendly. All the things you want a person to be… he is that. He's always ready to work.”

As far as dating goes, despite continued reports that Pitt is dating Massachusetts Institute of Technology professor Neri Oxman, the source assures ET that he is single.

“He has gone on dates but he’s not looking to leap into a serious relationship at the moment," the source reveals. "He is content on his own and enjoys the quality time he spends with the children when he isn’t working."

The source adds that Pitt “is focused on two of the most important things he should be focused on, and those are his children and his work. Being a father is his number one job and he knows that. He will always be there for those children.”

Additionally, the source also mentions that when Pitt is not with the kids or on the set, “He’s spending more time out and about socializing with his close friends, but he also is still a homebody and appreciates hanging around his place.”

Meanwhile earlier this month, Jolie was ordered by a judge to help repair their children's relationship with their dad. According to court documents obtained by ET, a judge determined that the kids "not having a relationship with their father is harmful to them."

In addition, the judge determined that it is "critical that each of them have a healthy and strong relationship" with both their parents.