Leonard: So, Mother, I'm surprised you came all this way for Sheldon's birthday.
Beverly Hofstadter: Oh, I was happy to. He did come to my 60th.
Leonard: Oh, you had a party for your 60th?
Beverly Hofstadter: Oh, I wouldn't call it a party. Just a few close friends. And your sister and brother.
Penny: You know, to be fair, we did get married in Vegas and didn't invite her.
Beverly Hofstadter: And I never did thank you for that, dear.