Rob Reiner and his wife, Michele, attended Conan O’Brien’s party with their son, Nick, and hours later, their bodies were found in their Los Angeles home. Reportedly, the former late-night host is feeling overwhelming guilt about what happened to his friends.

When Arnett heard that Conan’s dad Dr. Thomas F. O’Brien, a professor at Harvard Medical School, died at age 95 at his Brookline home last December, Arnett immediately texted his sympathies.