Okay, so for those of you who don't know, my friend Macaroni_Pizza has been having some problems; first, she really doesn't like changes and has a hard time dealing with her emotions. Second, she feels like her parents, even though they say they're always on her side, they seem to side up with her brother, who, according to her, is perfect in all things and is the pet of the family.

So, I've never seen them ineract, so, I have limitated data here.
But, I'm going to try to give you some advice, and hopefully, you'll learn a thing or two.

I don't have this kind of problem, so, I'm just going to have to do the best I can.
Also, I'm an empath, but, I understand that a lot of people aren't so great at seeing things of someone else's POV.

And, Don't take this as perfect advice or anything.

So, first, try and take out you emotions and let's look at the evidence.
These are some of the questions you should ask yourself:

How does he act towards them?

Aside from your suspisions, how do they treat him?
Is it really different than how they treat you?

What do they do for him that they don't for you?

How can you do better?

And here are some things you might do as a ressult of your investigation:

Ask them

Talk to a psycholigist if you can

Talk to them reasonably

Talk to a close friend or someone you trust

So, I hope that helps and I hope things get better.

Renx out!