He is indirectly mentioned in "The Cohabitation Formulation" when Leonard tells Raj that his sister is 38 and married when Raj said he would have his way with Leonard's sister because he wanted to get back at Leonard for going out with his sister Priya. In a previous episode, Beverly Hofstadter mentions that Leonard and Michael's sister is engaged, most likely to this man.
- Father-in-law: Alfred Hofstadter
- Mother-in-law: Beverly Hofstadter
- Brother-in-law: Leonard Hofstadter
- Brother-in-law: Michael Hofstadter
- Wife: Unnamed
- It is possible that this person could also be a woman, as Leonard never mentions a husband, since all he says is "My sister's 38 and married".