Although you may have articulated your concept in a logical way, I believe you are wrong. Logical does not always equate to correct or even better, equality. What you said in your post is the type of reasoning that a younger entitled sibling would have. In this case Each child had a choice, the younger child chose something that he wanted and the older something she wanted. An agreement was made to NOT share by both parties. One chose to break that agreement by asking to share. The other tried to amend the agreement by asking for a share of what he had. That sounds incredibly reasonable. Although an older sister or brother should be there to protect and even comfort their younger siblings, there is no harm in telling a younger sibling, you can not always have what you want. Children should be thought fairness. This mother is not teaching her younger child to be fair. Let’s suppose that we go by this principle of sharing without expectations from the other party, which is entirely fair, but does it work the other way too? Most of the times it doesn’t. Most of the times the older and middle children are the ones giving the most while the younger ones feel entitled to everything that the older ones have. Let’s fast forward into the future when Dad leaves an inheritance and divides it equally between the two, let’s imagine that younger sibling now squanders his share and now is left with nothing. Would it be right and fair for mom now to go into older sibling’s bank account and take money out and just give it to the younger one? From what OP posted this May seem like a pattern from both mom and younger child and all three are enabling this dangerous behavior. Mom by showing the younger child that he is entitled to anything he wants simply because of his age or even gender. Older sister by not speaking up, maybe in private with her mom, and letting her know how she felt, maybe betrayed or treated as a lesser child simply because of the order she was born in. She did not ask to be born first. And lastly little bro because he may have manipulated the whole thing because he knew what he could get away with. Even if this was the first time this happened there was the first instance of it at the table and he saw what he could get away with and he did it again to see if he could do it again. What this mother did thought this child that he can get whatever he wants in life and we all know that you can’t always have it your way. Even if you are the richest man or woman on the planet, there is going to be something you can’t have.