Things are Gettin' Serious for Carrie and Chace!

The couple at Marquee earlier this month

Things between country super-star Carrie Underwood and Gossip Girl's Chace Crawford are heatin' up!

Us says the duo spent Xmas at Chace's family's house in Dallas (a Texas boy, hmmm, seems like she has a thing for Cowboys), where, according to the mag, "his whole family loves her" and thinks "'Carrie Crawford' would be a great addition to the family!"

A source goes on to say that Carrie is completely over ex Tony Romo. "She thinks it's a joke he's with Jessica Simpson and sees him as a player. Carrie and Chace call him 'the player' and Jessica 'the ditz.'"

When Carrie Underwood's calling you names, that's GOT to hurt!