Mom is at sisters becking call but busy for me!, favoritism

[dbruce13]

First off I am a Dad not a mom. My mother has been great with my sister’s kids. At the drop of a hat she is there to rescue her. When her son was kicked out of day care she watched him extensively . When her daughter was born she made the comment she didn’t want here in daycare till she was a year old and watched her extensively. She still works as a home builder but changed her schedule around to help so much. Second my sister is a doctor and has so many options financial that we don't. My mother was working in another state and would send my dad home to help with her kids being apart for weeks at a time. Sense then my sister has gotten a full time nanny and they don't watch them as much. So she says. My sister went on two vacations this year and they kept the kids the whole time. Now the second trip the nanny kept them during the day but they kept them every night for a week from 5pm till 7 am and all weekend long. My sisters son plays baseball and at least the last two weeks if not more one of them goes to the baseball game and the other stays home to watch her 18 month old daughter because the game time conflicts with her nap time. My sister does a bible study and she watches them on Wednesdays even though daycare is available. They don’t want the kids to be up past their bed time so they watch them instead. The other day my sister and BIL went to a cowboy game and they watched them till 1:30am.
I don't think they owe me anything and have to watch my kids but they set such a precedent with her kids I guess I have expected some help. I told them my two month old cant go to our church daycare till she is 6 months old and asked for help once a week so I can do some work in the field. They are doing it for the last month but I have to hear how hard it is for them because after 35 years of building homes alone all of a sudden my dad has become a very important part of her getting her work done. They do it but I have to hear how much of a burden it is to them. I asked the other day for them to watch my kids when we got last minute cowboys tickets and I got that she had plans to go shopping. It was two days before my moms birthday and she wanted to shop. Well it was my wife’s birthday that day and she couldn't help me out. I don’t expect them to be care givers to my children but come on. Whey is it so easy for my sister and such a chore to help us? Oh one more thing my mom has been mad at my grandmother for 35 years for watching my cousins so much and not helping her enough. Talk about hypocrisy.
What should I do part of me want to be done with them and part tells me just take the high road and just know I cant count on them. I know they love my kids but seriously? What should I do I need some advice please.

[~Roo'sMama~]

I think I would try confronting her about it - which is NOT easy for me but it sounds like it needs to be done! Ask her calmly why she is able to watch your sister's kids so much but not your daughter. And maybe remind her how upset it made her when your grandmother could never watch you - she might not realize that she's doing the same thing.