Kevin Federline and Britney Spears just agreed to a new custody agreement, and now we might have some insight as to why.

As The Blast reports, the pop star's ex-husband filed a police report against her father, Jamie Spears, on August 25 alleging that he had physically abused their 13-year-old son Sean Federline. TMZ was able to obtain more details, reporting that the incident happened on August 24 when Sean was visiting his grandfather's home in Ventura County. Sources say the two got into an argument, and Jamie put hands on his grandson. He allegedly broke down a door to get to Sean and grabbed him once he was in the room. There were no visible bruises or injuries to the child; however, Kevin found the altercation serious enough to report to the authorities. Jamie is currently under open investigation.

The news comes the same day Kevin and Britney filed court documents adjusting their custody agreement, which now grants the dancer 70 percent custody of their children Sean and Jayden James. Their prior arrangement was a 50-50 split.

Though the singer's mental health struggles might have something to do with the new agreement, the fact that this alleged incident between her son and father happened during the kids' time with her can't help.

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