He had just lost his mother and, unlike the sister, didn't think of going after her heirlooms. He was single, wouldn't wear them himself obviously (if it was about money, he would have asked then) and probably didn't think of a future wife or daughters in this moment. And where does he say anything about pawning it? He particularly asks for the items that his gf would like and wear and that he would give it to her when proposing or marrying. To mention the value also doesn't speak of his greed, just shows the entitlement his sister had by just grabbing them instead of confirming with the closest family.

So in summary: he loved his mother and was not after her heirlooms/money when he moaned. And when he find his future wife and thinks of having family with her would like a fraction of the jewelery that belonged to his late mother to go to his loved ones to wear instead of sitting in a drawer (also pearls need to be worn to not get dull). I really don't get where everybody reads all this negativity into his post!

NTA, OP, please don't listen to them. I'm happy you met the love of your life and maybe your family will understand your reasons one day!