It's almost time for the sixth drama-filled season of The Hills to begin (premiering on MTV Tuesday September 29 at 10:00 p.m. ET!) but today it's all about Heidi Montag who is celebrating her 23rd birthday! Heidi just Tweeted that this will be the best birthday ever with her hubby Spencer by her side and a new dog! Happy Birthday, Heidi!

Fun Facts About Heidi:
-A hidden talent Heidi discovered while filming her music video for "Higher" with Spencer was how to do a good bird call to the surrounding seagulls!
-Heidi and Lauren Conrad became friends after meeting at freshmen orientation in college when Heidi approached LC to chat!
-The Hills isn't the first MTV reality show Heidi was on -- she also appeared on a couple episodes of Laguna Beach!

Leave your happy birthday wishes for Heidi below!

Photo: Courtesy of MTV