Yep, started with my mom when me and older sis were pregnant at same time. At xmas, I was 4 mos along. Dsis was 6 mos along. Her unborn child got a huge stack of gifts. Mine got the promise "well we'll have a shopping trip when you are further along." Never happened. But I didn't expect it to.
This is not just a favoring of grandkids though, my mom has always favored certain of her own children and carried that over to THOSE kids' kids. We had a heart to heart about it once. Her excuse was "You were the only one we never had to worry about." No mom, every girl needs a mother.
I live 2 traffic lights and 4 miles from my mom, for the past 8 yrs. She has NEVER...let me reiterate...NEVER babysat a single one of my 4 children for a single minute. Ever. She has, however, taken my youngest sister's son for days at a time. Picks him up out of the blue to go see movies. Goes to WDW and brings only him a souvenir (an enormous stuffed Eeyore). My brother (now 10yrs in the Marines) was a true terror. But he was always mom's favorite. Now he is her trophy for doing a great mothering job. His visits, therefore, are treated like celebrety sitings and much spoiling goes on. Yes it hurts, yes my kids notice. But it is how it is. I keep up a relationship with mom. My kids see her more, because I invite her to dinner often.
My grandmother (dad's mom) knew how bad things were for us growing up, so really "saved" us. She died in 1995, and I will never forget how she was. She took extra care with me and my siblings, but never left my cousins feeling less loved. We ALL mourned and still mourn her passing. My cousin and I approached her once and my cous asked who her favorite grandkid was. She replied "Whoever needs me most at the time." That made NOBODY her true favorite, in our minds. We just accepted that maybe we were the ones less in need at a given moment, if we saw another grandkid getting special treatment.
As for what I say to my kids: I take a page out of my grandma's book. I just say that Aunt Ari is getting Grandma's help right now.
Beth