Britney Spears' ex claims she'd stand 'silently' in sons' rooms at night 'with a knife in her hand'

The father of Britney Spears' two children has made a shocking allegation about the pop star, claiming she'd stand 'silently' in their rooms watching them sleep 'with a knife in her hand'.

In Kevin Federline's upcoming memoir, titled You Thought You Knew, he alleges that the 43-year-old would sometimes enter their sons’ bedroom at night while holding a knife, and just stand there watching them.

The 47-year-old, who was married to Spears between 2004 and 2007, shares two sons with the pop icon - Sean Preston, now 20, and 19-year-old Jayden James.

"They would awaken sometimes at night to find her standing silently in the doorway, watching them sleep - ‘Oh, you’re awake?’ - with a knife in her hand," he writes, per an excerpt seen by The New York Times.

"Then she’d turn around and pad off without explanation."

Kevin Federline was married to Britney Spears between 2004-2007, and they share two sons (Jason Merritt/FilmMagic)

The memoir paints a worrying picture of the Mississippi-born singer's mental health, with Federline expressing deep concern over her current well-being.

"It’s become impossible to pretend everything’s okay. From where I sit, the clock is ticking, and we’re getting close to the 11th hour," he writes.

"Something bad is going to happen if things don’t change, and my biggest fear is that our sons will be left holding the pieces."

The mom-of-two has made headlines in recent months due to a stream of erratic Instagram posts - often showing her dancing in her underwear, and sometimes seemingly sending cryptic messages.

In his memoir, the Californian dancer also calls out the #FreeBritney movement, suggesting that while fans meant well, the outcome may have done more harm than good.

Spears with her youngest son Jayden, now aged 19, pictured together earlier this year (Instagram/@britneyspears)

Spears was under a conservatorship of her dad for 13 years, which meant he was her legal guardian and controlled her personal and financial affairs.

After the fan-led campaign brought widespread attention to her situation, the conservatorship ended in 2021.

"Now, more than ever, [our children] need your support. I’ve been their buffer for years, but now it’s bigger than me," Federline added. "It’s time to sound the alarm."

The 'Toxic' hitmaker's team has since responded to Federline's claims.

"With news from Kevin’s book breaking, once again he and others are profiting off her and sadly it comes after child support has ended with Kevin," Spears' representatives said in a statement to PEOPLE.

The singer's relationship with her two sons has been complicated over the years (Instagram/@britneyspears)

"All she cares about are her kids, Sean Preston and Jayden James and their well-being during this sensationalism. She detailed her journey in her memoir [The Woman in Me]."

Federline was given full custody of their kids in 2006, with the '...Baby One More Time' songstress paying him child support until their youngest turned 18 last year.

Federline’s tell-all memoir is earmarked for release on Tuesday, October 21.

UNILAD has approached Spears' reps for further comment.

If you or someone you know is struggling or in crisis, help is available through Mental Health America. Call or text 988 to reach a 24-hour crisis center or you can webchat at 988lifeline.org. You can also reach the Crisis Text Line by texting MHA to 741741.