My mom never wants to babysit

Today I was at my moms house and both of my sons wanted to stay at my mom house .(ages 7&11) & my mom and 3th sister straight out said no and I felt so bad bc my kids they want to be with her nd my sister that came from deployment . When I would’ve

Picked them up tomorrow so they would only have to deal with them for a day . I know it’s not mandatory but It make me think if I had my grandkids ask to spend the night I would have them over . I feel like they push my kids aside and my other 2nd sister she has a kid and my mom and my 4th sister watch her son . This just make me want to distance myself.