Your brother is certainly displaying double standards, but it's not unusual. Siblings can be the worst for recognising the value of family relationships.

Relating to my own experiences, has he always been like that or has it happened when he got married (for instance). My brother changed when he married for the second time. She controls and tries that behaviour on family too. For ages, he couldn't be bothered to do jobs for our mother, because he was too busy helping his in-laws.

He recently told me to wind my neck in when I contested something he said about me. I know where the comment had originated but this made me more wary of him. Unfortunately, he's adopted the attitude of both his wife and stepdaughter, who think you should tolerate unacceptable behaviour because of everything they've done for you. What they've conveniently forgotten is time spent packing up for their move while new niece was in hospital, then helping with decorating in new house (amongst other things).

Sorry I've taken over this thread but wanted to give you an example of that type of behaviour. If your brother feels it's more important to take a holiday, then that's his choice. It would be better if you don't react. Just because he's your brother, it doesn't mean you have to behave in the same way!

Enjoy your daughter's graduation and take pride in her achievements.