Alexis Houston - Matt Lauer Mistress ?

Photo: Alexis Houston

'Today Show' host Matt Lauer has reportedly split with his wife, Annette Roque Lauer amidst reports of infidelity in their 12-year marriage.

Annette reportedly accused Matt of cheating on her while covering the Winter Olympics in Vancouver, British Columbia this past February.

There's been a lot of buzz about Matt Lauer's alleged mistress since The National Enquirer broke the story.

According to Hollyscoop, Matt was carrying on an affair with Whitney Houston's half sister Alexis Houston, who is a young singer/songwriter/producer.

Matt and Alexis met on the set of The Today Show. She would often attach herself to charities that Matt was involved in so they could spend some time together. "We all saw through it," a source said.

"Everyone on set knew about his affair," the source added.

in March 2008, Matt's staff reportedly booked hotel and air accommodations for Alexis, so she could accompany Matt to South Carolina. "They often stayed in the same hotel, but on different floors," says the source. Alexis also accompanied Matt on a trip to Los Angeles that summer.

Lauer is no stranger to cheating scandals. In 2006, Annette, pregnant with the couple's third child, filed for divorce after learning of an affair he was having with a married woman in 1998, just months before their wedding. She withdrew the divorce petition after one month.

UPDATE: Alexis Houston has denied the rumors of an affair with Matt Lauer.