A moody mark - a person who is always in a bad mood because they have kids,

a person who is always in a bad mood because they have kids, especially the one who thinks they’re the most important person on Earth

I just got yelled at by my kid. I’m a moody mark.

My kid won’t stop drawing on the walls. I’m a moody mark.

I’ve had it with my kid’s attitude. I’m a moody mark.