Well maybe I'm lucky.
I'm an oddity Hispanic and was an only child, so no sibling rivalries to deal with
My second cousins, it's all good with them, but they are second cousins so it's always arms length so to speak.
Parents, who I did have a great relationship, long dead, but I still miss them.
But my kids are bringing me the next generation, and I so much enjoy being Grandad, all the fun without the changing diapers and sleepless nights lol
That all being said, and I think it's a function of being an only child, I learned to be very self sufficient.
Don't get be wrong I love my family, but I could function completely alone and never miss a soul