A: No, you should just have the turkey!
Explanation: Another joke that plays with a double meaning. Imagine a conversation like this: “What did you have for dinner?” “I had soup and bread.”
“To have _____ for dinner” is to eat whatever you put in that blank space. Yesterday I had turkey for dinner. I did not have my family, that is, I did not eat my family (thank goodness!).
To “have your family for dinner” can also mean to invite them over to eat dinner with you. That is why the joke is funny. The listener is expecting advice on whether or not to invite the family over for dinner. The answer shows that the questioner had a different meaning in mind. It reminds me of a Twilight Zone episode, To Serve Man.
Happy day after Thanksgiving! And no, I am not going shopping.