Being a Grandma is a whole lot different than being a mom. The little people God sends along "belong" to us, but not really. It is not Grandma's job to decide when Baby will start eating solids, when he will be potty trained or whether he will attend preschool. Sometimes we do things different than Mommy or Daddy. It's not because we are trying to spite them or prove our way is better, it's just because we are different people. Grandma hasn't neglected Baby because she changed his diaper less than Mommy or let him cry himself to sleep. She knows that diapers are expensive and when her own children were small, she changed diapers only when they really needed to be changed. And crying never hurt Baby, it taught him to settle himself when other tasks were calling, at least in Grandma's days as Mommy.
Grandma doesn't mind if Mommy wants to put Baby on the potty several times throughout the day, she just isn't ready to do that herself. She just found potty training less of a struggle when she waited and prefers to fight other battles right now. Grandma walks a fine line never knowing when her advice or opinion are needed, wanted, or appreciated. She's doing the best she can to do things like Mommy would, but sometimes its hard to know just what that is.