Bottom Left. I don’t think Brian had to act too much there. He’s known Lea since she was 10 years old. The little girl who barely had a line in Ragtime (even though she was on stage a lot with her “dad”) and now she’s this bigtime TV star.
He said in the blog post he wrote when he got the part how he had watched her mature from Ragtime, to Fiddler on the Roof to Spring Awakening to Glee.
Playing a proud dad wouldn’t be a stretch watching her up on stage.