Heigl Refuses To Marry Without Knight

Actress Katherine Heigl is so close to her Grey's Anatomy co-star T.r. Knight, she has refused to get married without her "brother" by her side.

The Knocked Up star is to wed her fiance, singer Josh Kelley, later this year - but she was so adamant Knight was present at the ceremony she has planned her December 23rd nuptials around his work schedule.

A source tells Us Weekly, "(Knight's) a brother and a best friend to her."

"She wouldn't get married without him."