We didn't see that one coming! After dating quietly dating for more than six months, Avril Lavigne is engaged to fellow Canadian musician Chad Kroeger. A rep for Lavigne told People on Aug. 20 that the Nickelback frontman had popped the question. The couple got close after collaborating on a song for her upcoming album, and they started dating in February (shortly after Lavigne split from Brody Jenner). "A romantic relationship blossomed as they spent time writing together," a source revealed. Kroeger proposed Aug. 8 with a stunning 14-carat diamond. "He makes her so happy," a family source said. "Both of their families could not be more excited." This will be the second trip down the aisle for Lavigne, who was previously married to Sum 41 rocker Deryck Whibley.