11/20/2012 11:48 am ET Updated Nov 21, 2012

Britney Spears & Kevin Federline's Exes Are Dating (REPORT)

Here's a weird love ... square?

Britney Spears' ex-husband, Jason Alexander, is dating Shar Jackson, the baby mama of her second ex-husband, Kevin Federline, according to RadarOnline.

A "source close to the situation" revealed that Federline's former fiancee (whom he dumped while she was pregnant with their second child for Britney back in 2004) is now dating Spears' first husband and childhood sweetheart, whom she was married to for 55 hours in 2004, before they had it annulled.

The source told RadarOnline that Alexander and Jackson met at a gifting suite in Los Angeles years ago and have been friends ever since, but they recently decided to take things to the next level. According to the source, Alexander has been by her side following a number of tragic events, including her assistant's suicide and her friend passing away from cancer.

Spears and Federline also married in 2004 and divorced in 2007. They are now on good terms following a bitter custody battle prompted by Spears' breakdown in 2008.

The 30-year-old pop star is currently planning wedding No. 3, though there have been reports her relationship with manager Jason Trawick is on the rocks. A rep for the couple denied the claims that Trawick has no plans to follow through with the wedding.

The timing of reports that Spears' relationship is in trouble and news of her ex's new relationship could be coincidental, but we couldn't help but notice that it sounds a lot like what Alexander was spouting back when Britney first became engaged to Trawick in 2011.

"Sort of a nice way to sew it all up, she marries her handler," Spears' first husband told Us Weekly. "I think it's fake and I think people are afraid to say it."

Britney Spears Through The Years