Wa `alaykum As-Salamu waRahmatullahi wa Barakatuh.

If your father knows that his other children are grown up and independent and can support themselves and you are not able to do so because of your age and station in life, and you are the only one taking care of him, then he is allowed to buy you a home for you to support you.

That is not considered, according to the best of my judgment, discrimination against his other children.

First of all, I understand they are independent and able to support themselves;

Secondly, they are not taking care of their dad, and you are doing so.

Therefore, you need not feel guilty over this.

Having said this, you should do your best to continue to foster ties of kinship with them.

Almighty Allah knows best.