Credit: Katherine Heigl Twitter

One of the things we love most about the Grey’s Anatomy cast is that they’re all such good friends off screen. And over the weekend, Katherine Heigl — the artist formerly known as Izzie Stevens — attended the wedding of another one of our favorite Grey’s alum — T.R. Knight (George O’Malley)!

Katherine tweeted a pic of herself posing with a pal, pre-wedding festivities — and she looked amazing in a lacy red cut-out dress and matching red lipstick. “My bestie Chey and I perfecting our disenchanted fashionista pose before attending a wedding in upstate NY,” Katherine said.

T.R. married longtime boyfriend Patrick on October 4, celebrating their nuptials with a “small and quiet” wedding. We love the fact that these two keep in touch and remain such good friends — it’s a suitable compromise considering how much we miss seeing the George and Izzie dynamic on Grey’s every week.

And speaking of seeing Katherine on TV again, she’ll be making her return starring in (and producing) a new CIA drama from CBS. The series is so far untitled — we may have to wait until 2014 to see it — but could be an awesome way to turn her career around as she returns to her roots on a TV drama.

Do you love Katherine’s wedding look? Sound off below!