Kristin Cavallari's 'Hills' co-stars congratulate her on becoming a first-time mom

Since Kristin Cavallari gave birth to her son Camden Jack Cutler, the reality star has sent a tweet to her followers assuring that she’s fine and resting at home.

On Wednesday morning, Cavallari tweeted “We are thrilled to welcome Camden Jack Cutler into the world. He was born this morning weighing 7lbs 9oz. Everyone is doing great!"

Cavallari’s former Hills co-stars Audrina Patridge, Heidi Montag and her husband Spencer Pratt have all tweeted their congratulations to the new mom.

"Congrats!!!!!" Patridge wrote. "Can't wait to see Camden. So happy for you!" Us Magazine reports.

Montag wrote "Congratulations on your new baby boy! One of life's greatest gifts! Enjoy mama! Oxxo." While her husband, the former Hills “villain” as he has been referred to as, wrote "Congratulations on Camden's birth!"

He even offered, “I'm free to be the Godfather if you need one!"

Cavallari is engaged to Jay Cutler, whom the new mom gushed about before the birth saying he’s “gonna be a great dad! He's so cute with kids...He's good with my little dog, so he's gonna be really, really cute with kids!"