Brad Pitt ‘Aware and Upset' Daughter Shiloh Dropped His Last Name, Says Source: 'He Loves His Children' (Exclusive)

One week after Angelina Jolie and Brad Pitt's 18-year-old daughter Shiloh filed to drop "Pitt" from her last name, a source close to Pitt tells PEOPLE that the father of six is "aware and upset" about the change.

“He’s aware and upset that Shiloh dropped his last name. He’s never felt more joy than when she was born. He always wanted a daughter," says the source.

"The reminders that he’s lost his children, is of course not easy for Brad. He loves his children and misses them. It’s very sad," adds the insider.

"He’s still happy with Ines [de Ramon]," the source continues, but the distance from his children "pains him."

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“He still loves all of his kids tremendously,” another source close to Pitt tells PEOPLE. “This whole process has been very hard for the whole family."

As previously confirmed to PEOPLE by someone familiar with the matter, Shiloh’s documents were filed on Monday, May 27, which also happened to be her 18th birthday. The teenager is requesting a new legal name, hoping to go by simply "Shiloh Jolie."

Jolie, 48, and Pitt, 60, share six kids: Maddox, 22, Zahara, 19, Shiloh, Pax, 20, and twins Knox and Vivienne, 15.

Shiloh isn't the only child of Jolie and Pitt to appear to go by a different name. In the Playbill for the new musical The Outsiders, which their daughter Vivienne helped mom Jolie produce, the teenager is listed as “Vivienne Jolie" instead of "Vivienne Jolie-Pitt," PEOPLE confirmed.

At this time, it is not clear if Vivienne has also legally changed her name. 

Last November, while joining the Mu Pi chapter of the Alpha Kappa Alpha sorority at her university, Spelman College, the former couple's eldest daughter Zahara introduced herself as “Zahara Marley Jolie,” a video shared by Essence showed.

All three apparent name changes come after years of reports of strain in Pitt’s relationship with his children since Jolie first filed for divorce and sole physical custody of their kids in 2016.

In August 2022, a Pitt source told PEOPLE that the actor was hoping to soon reach a better place with his children amid the exes’ ongoing custody battle. They explained that “it's been a sad situation for years.”

“Since Angelina filed for divorce, Brad has been focused on having the best relationship possible with his kids,” the insider said. “It's been very difficult for him. Many times, there have been long gaps where he didn't see the kids at all."

In a recent filing in the dispute over their winery Chateau Miraval, a former security guard for the couple, who still works for Pitt, claimed in legal documents obtained by PEOPLE that Jolie allegedly “encouraged” the children to “avoid spending time” with Pitt during visits. 

Paul Murphy, an attorney for Jolie, subsequently told PEOPLE that "all Angelina has ever wanted was separation and health, with positive relationships between all members of their family, including Mr. Pitt."