I'm surprised she wouldn't be a little more appreciative that you have such a well trained/behaved dog. I mean, would she rather her use the bathroom somewhere in the house?? Why wouldn't she want pp pads? It's only while you are there.
I can understand if she would rather Bailee go outside..anyone would. But they should praise you for being responsible enough to have a backup plan, in order to respect their home as much as possible. Also, anyone with a small dog and a small child should always be watching them closely at all times. Do they not know just how fragile a small dog's bones are?
Like others suggested, you could talk to your dad and just let him know your feelings, that you are trying to be and are a responsible dog owner and you would think they would respect that. Hopefully, it can be worked out quickly so there's no tension and you all can enjoy the holidays!
Good Luck