There's a phenomenon for this. When you have to watch and care for someone everyday and allday you get annoyed and frustrated more, vs someone who occasionally does. She gets annoyed probably because she's in charge of everything in the house + the kids. So she's not just watching the kids all day, doesn't have time to game and go box. Probably had to cook, laundry clean then clean again while yelling at the kids to get down. To her it's a full time job. To fathers it's babysitting.

Tbh I was raised raising my cousins and it might get annoying at times but it’s pretty easy as kids can play with each other and if you are interesting enough it’s easy to keep them entertained and you can do 15 min “cleaning break” every 45min or so