Kiernan Shipka had quite the star-studded birthday party!

The Chilling Adventures of Sabrina star turned 20 on Nov. 10 and, to commemorate her big night, the actress shared a handful of adorable pictures to her Instagram. Along with BJ Novak and David Dobrik, guests included her TV boyfriends Ross Lynch and Gavin Leatherwood, as well as her real-life love Christian Coppola. But, of all shots posted to her social media, the best of all was her reunion with Mad Men co-star Jon Hamm.