Brad Pitt
Brad Pitt and Angelina Jolie split in September 2016 Juan Medina / Reuters

Brad Pitt is "really hurt" as he was not invited to son Maddox's birthday party. The Allied star's eldest child turned 16 years old on 5 August.

According to HollywoodLife, the Oscar-winning producer is "upset" with his former wife Angelina Jolie after she did not invite him to his son's big bash, which he feels is the "first big milestone event since the divorce" he has missed out.

"Angelina is planning a big sweet sixteen party for Maddox this weekend and Brad is disappointed he is not invited to attend. Brad is upset that he will miss out on this first big milestone event since the divorce. He is doing his best to work around Angelina's wishes for the children, but this is one instance where Brad is really hurt," a source close to the family told the celebrity gossip website.

Jolie reportedly planned the event, with Maddox and his few friends getting together to celebrate the big occasion.

"Despite his pleading, Angie simply will not set aside her differences, put the past behind her and get together with Brad for the kids. Maddox is going to have a few friends together and Angelina is arranging everything to make his 16th birthday special and Brad wants to apart of the big day. But is not going to happen, so this birthday will be another reminder to Brad that his family will never be the same," the source said.

Although Pitt was not invited to the big event, the 53-year-old actor has reportedly told Maddox that he can also throw a party for his son, with whom his relationship is said to be estranged following an alleged heated argument on board a private plane that led Jolie to file for divorce in September 2016. Pitt was grilled by the LA County Department of Children and Family Services and the FBI and was later cleared of the allegations.

"Brad has made it clear to Maddox that he too can throw a party for him and they can do whatever Maddox wants...but they both know it won't be the same," the source said.