She is 18mo older than I and has a 13yo girl and 7yo boy.
I'm glad you are able to see this is your sister's problem, not yours.
Your sister is acting like a jealous sibing...go figure...lol.
Thank you for your response.
Has your sister always been jealous of you?
Your sister is acting like the spoiled brat here. My, my is jealousy ever the green-eyed monster! I think you correctly identified the source of the problem: her kids no longer have the spotlight and she's displaying her jelousy and immaturity by acting like a high school girl who didn't get asked to the prom.
A couple of things:1)You were absolutely correct to pull your daughter out of her daycare for valid reasons. I would not leave my less-than-2-year-old child with a teenager for all the tea in China. Your sister is opening herself up for massive liability by putting a kid in charge of kids. (And don't think for one moment if something happened to the children in her care that the parents of said children wouldn't sue her out of existence if anything happened to their kids!)
2)Your sister is accusing you of the things she is doing: favoring her children, finding fault with yours, accusing you of attending family events for someone other than the guest of honor. These are all things SHE has done. It's typical behavior for a manipulator.
My advice? Stay in touch with your parents. Attend family events whether or not your sister is invited or whether she's trying to control others by saying things like, "If you invite my sister, I'm not coming." In those cases the best thing the inviter can say is, "We'll miss you then because we've invited your sister." Let her choices be her consequences, not yours.