I'm sorry!! I left my guys home for one family party because there were just too many people there, but it was nearby so we weren't gone all day. Last night we took them to my parents' house (only 8 people there) and my mom and dad and brother are watching them for us while we go to the in-laws all day today. My in-laws "invited" them to sit in a crate the whole time in a bedroom - um, no fun for us OR the dogs so they are going to Camp Grandma for the day and they will have so much fun
If it means she has to stay home alone, I would call your mom and tell her you can only stay for 2 hours because the puppy can't be left alone longer than that. Tell her you have to find out exactly what time she is serving food because you can't wait around all day... etc. She might change her mind
Bring a sling if you have one so she can be carried around and not be underfoot the whole time. We brought our crate yesterday and put the dogs in there while we ate. Sammy is quite the pest begging for food and I didn't want to be rude and I didn't want them to eat something they shouldn't. It worked out great. Maybe that would help mom be OK with it?