Yes he can have memories of kids taunting him in school . Remember that he was abandoned at birth
Have issues like she fought with my father and I suffered in anath ashram .. but yeh jadugarni
Yes, the reason would be more than enough to be clinging to adoptive mother and family and rejecting Sai, first to show anger for abandoning him and the fear that she could leave him again. They can also show sibling rivalry too, with Vinu thinking whatever love he deserved Savi got but nahi jaadugarni kheeche jaao.
Ghum makers really have a mark in frustrating audience...they made a SaiRat kid so irritating, that we are on the brim to lose patience with him.