Unaware He Has Become The Joke

(My dad is a little slow on the uptake. Sometimes it takes a long time for him to get a joke. My mum and I were talking about it one day.)

Mum: “[Friend] just told me ‘Wow, your husband is very steady! I told a joke and everyone laughed but he managed to keep a straight face!'”

Mum & Me: *together* “It must be because he didn’t realise that it was a joke.”