ACTOR KNIGHT WILL BE BRIDESMAID IN HEIGL’S WEDDING

She may be tired of her relationship with him on Grey's Anatomy, but in real-life, Katherine Heigl can't get enough of T.R. Knight.

Not only did he help her celebrate her recent 29th birthday, but Knight, 34, reveals in the current issue of Us Weekly that he'll be in his Grey's Anatomy castmate's wedding party.