My grandmother is judgemental, , and doesn't care about certain grandkids?

My grandmother has always been extremely about cleaning and making sure everthing is absoloutely perfect. She also has an extremely stuck up attitude about other people and is very critical of everyone, and loves to brag about certain granchildren that she must think are perfect (they are in balet recitals, sports, and in expensive colleges, some becoming areospace engineers) etc. However, some of us grandchildren with bad luck and are actually human and not perfect, she never speaks about to others. My brother who has had horrible luck and is 25 and struggling for financial security, she looks down upon him like he is less than she. he even just had major surgery and she has not come to visit him or call him. She never visits another grandchild who was in a drunken car crash when she was younger. Everyone makes mistakes, but what is her problem? DO you think she favors the "perfect" grandchildren over us mistake makers? Why is she so stuck up like this?