Is there a way to let go?

[Rosebel]

I have posted about similar issues before. The problem being my sister or more accurately my dad.
She is and always has been his favourite child. In some ways it no longer bothers me as I've lived with it all my life.
When I had my eldest she really was the favoured grandchild, maybe because she was the first girl. Anyway that only lasted 2 years before my sister also had a baby. As the favourite child it was perhaps natural that her child would become the favourite and mine would be an after thought.
Now the kids are teenagers and I'm still (obviously) carrying a lot of anger about the obvious favouritism but I want to let it go.
My dad is in his 70s and his health is okay but not brilliant. I know he won't live forever and I don't want him to die while I'm feeling this way (he doesn't really know how I feel).
AIBU to ask is there an easy way to let go of the anger and resentment?

Anyone?

Talk to him about it. I certainly would. Ask him why he has favoured your sister. If you don't it is always going to bother you.

I’m afraid you’ve said the one word that I don’t think you can let go of, it festers, and that’s resentment.
Would you consider having some counselling to see if that helps ?

He won't admit to having a favourite even though it's obvious to everyone.
I do love my dad and I hate the thought of him dying while I feel like this. I know I'd feel guilty.
I spent most of my teens trying to be just like my sister to try and be favourite or at least equal but it didn't work.
Luckily my kids don't try and copy their cousin but they have said for a long time that x is grandads favourite and it's sad. My dad doesn't see it though or maybe he does but doesn't want to admit it.

Even if he doesn't admit it , he'll know you know.

There is a book called Cain's Legacy about sibling relationships with some helpful info at the back. If you google it on Amazon etc it may help you. It is hardback so not cheap but has helped a lot of people it seems.

There is not much out there on sibling jealousy, rivalry and the ways in which sadly, some parents play kids off against each other. The book might be a place to start to understand and process some of this.

You would also I believe struggle to find a counsellor who specialises in it as not much has been written about it.

I may be mistaken on this point so will watch this thread with interest in case anyone else has come across anything.