Kelly Osbourne is reportedly secretly engaged to boyfriend Matthew Mosshart.

Mosshart popped the question several weeks before Christmas after dating the former reality TV star for about one year, Us Weekly reported.

The pair is reportedly "really excited" about their engagement, according to a source, and have started planning their alleged summer wedding in the U.K. already.

"Kelly is the happiest she's ever been," an Osbourne friend told Us. "Her career is going well, and she's in a healthy relationship with a wonderful guy."

The 28-year-old former The Osbournes star and Dancing with the Stars participant reportedly has her clan's stamp of approval on Mosshart.

"Matthew is a stand-up guy," said a source close to the Osbourne family -- which includes former America's Got Talent judge Sharon Osbourne, father Ozzy Osbourne and siblings Jack Osbourne and Aimee Osbourne.

"They're so excited!" an insider told Us.

Osbourne, who currently co-hosts E!'s Fashion Police, and Mosshart reportedly met at model Kate Moss' wedding in July 2011 and were first spotted together in public kissing on the streets of New York in December of that same year.