Gym Christmas Puns

I have a scrawny, little, younger sister and we always have a seafood buffet for Christmas dinner.

Sister: "Hey, dad can you pass me the shrimp and I want some mussels too please?"

Dad: "Here's the shrimp, for mussels you're gonna have to go to a gym and do some exercising" [continues eating his food without ever passing the mussels]

Sister: "Hey, dad....."

Pops: "Hay is for horses, this is seafood."

This was especially funny due to the fact that he kept a poker face the entire time and never made eye contact with my sister, being completely serious and never cracking a smile. These exchanges happen at least 7X a day.

The headline on our local paper yesterday said, "Giving the gift of guns." My husband stared at it for a second, then said, "I guess a lot of people want gym memberships for Christmas."

/r/dadjokes I need your advice.

I was talking to my friend today, asking him about his plans. He casually told me "I might go to the gym, but probably not, I'm running late". To which I replied "Well, you can run a bit later!"

What does this mean? Am I a dad now? Has that girl I slept with at Christmas time had a baby and not told me?

Thanks for your advice!