Does anyone have experience with grandparents favoring another grandchild more than your own?

How do you handle it?

My parents favor my sister kid over mine. Which I kinda understand the bond they have with him is greater because he and my sister lived with them for almost 2 years. I dont have an issue with them favoring him except for when it becomes totally noticeable in front of my son. Hes 2.5 and he definitely feels it at times.

I had to have a talk with them a while back and afterward my mom got better my dad never really did but now it's really bad again. They blame me. They said it's because I never let them watch him when he was a baby. Which that is true and maybe is a factor but in my defense my mom wasnt in a good place to care for him at the time and even if that's the case I dont feel they should take it out on my son. He has done nothing to deserve the way he is treated when his cousin is around.

I have tried getting him one on one time with them but it only works out occasionally and alot of the time they end up trying to get his cousin to come too.

What am I supposed to do? He loves them so much but hes constantly getting his feelings hurt.