Family drama - AIO

For context, I have 45 first cousins and 16 aunts and uncles on my mom’s side. My family grew up close but have since lost touch as there’s been a lot of drama between my mom and her sisters. There’s not a week that goes by where I don’t know who is talking to who/who is shunned/etc. 

I have 3 kids in fall sports and when I got one of my cousins baby shower invite that is being at hosted at her moms (my aunts) house, I asked if my 7 year old daughter could attend because she saw the invitation. I was willing to let her skip her soccer games and a birthday party so that I could go to the shower while my husband and mother in law got my boys to where they needed to be. Apparently my mom and aunts think some of my cousin’s kids (all similar ages to my daughter) are “weird” so no kids are allowed at wedding or baby showers. I said that is an incredibly toxic thought to have about kids in your family and I would not be able to attend the shower because logistically there was no way to work it out. 

My mom has since made it her full time job to call/text me everyday about how I need to be at the shower because “family is family” and it isn’t a big deal to have my kids miss their games. I understand my kids are not competitive athletes at this point but they look forward to their Saturday games all week. Am I overthinking this and being too emotional because my mom has a pattern of doing this so I’ve built up a wall or am I justified in putting my foot down that I refuse to make my kids skip their games so that I can go to someone’s house for a baby shower that my daughter is not welcome at?