That might be so. It went around once that the younger of those two acted extremely selfish, rude and demanding about her birthday presents to her mother so she could get either equal amount or more than what her sister got for her birthday.

Since my imediate family and current living situation is one with mostly without money I imediately feel guilty for buying things I even need. I shouldn't but I do.. and those feelings leak into my responses toward my better off family who ask me (rarely) what I want for my birthday or Christmas.

I once told my Aunt how I felt about her favouritism and her response was that because she had a better relationship with their mom than mine.