Earlier this week we told you that Kevin Federline, who share sons Sean Preston and Jayden James with ex-wife Britney Spears, filed for a restraining order against Britney’s father, Jamie Spears after he allegedly had an “altercation” with Sean. Not only did Federline file for the restraining order on behalf of his sons, but he also petitioned to have his custody agreement with Spears officially amended from a 50/50 split to a 70/30 split in favor of himself.

While many may assume that Britney would side with her father, sources tell E! News that she is supporting her ex-husband. Britney was at her father’s house for a visit with her sons when the alleged altercation took place. "Britney was very upset with her dad and left with the boys. She never wants Jamie to treat her boys the way he did or to get involved with disciplining them in that way."

Federline's lawyer, Mark Kaplan, explained to PEOPLE what allegedly happened during the incident between the elder Spears and Sean Preston. “There was a disagreement that occurred while Britney and the children were visiting with Jamie at his home that led to a physical altercation that was observed by Jayden,” Kaplan told the magazine. “Britney did the right thing and removed the children and took them out of there, but the trauma to the kids is nonetheless.”

The source also stated that it was Britney who told Kevin about the alleged incident. "Britney had to explain to Kevin what happened and he felt they had no choice but to go to the police," the insider explained to E!. "Kevin wants to protect his boys."

Britney is also upset because, as the source stated, she feels that the incident could adversely affect her current custody situation since Jamie still has conservatorship over his daughter. "Britney is extremely anxious and paranoid about losing custody and she feels Jamie put her in jeopardy."

Kaplan assured E! News that Federline has no plans on keeping his sons from seeing their mother. "Kevin in no way wants to prevent the boys from having any unreasonable custodial contact with their mom."

Spears hasn’t commented publicly on the alleged event, but just yesterday posted a video to her Instagram account writing, “On a much-needed vacay by myself !!!! "

The singer recently changed her hair color from her usual blonde to a much darker shade of brown, causing many fans to worry that the change is a result of some personal turmoil.

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