2 yrs and 9 months old toddler attachment to toys
My son (2 yrs 9 months) used to have very good interaction with other kids, he used to sing rhymes with them, call them to play at his 2 yrs. A while ago (9 months back), my cousin's son (3 years at that time) hit, bite and kicked my son with in 15 seconds it all happened, my son cried whole night. And from that night, he stopped interacting with other children even if other kid is new and gentle, my son simply do not do any thing he just acts like other kid is not with him.
Recently in a play grounds, he had same experience with a 4 years old kid, Now my son scared of standing next to new child, he maintains at least half a feet distance with other kids. If a child approaching my son faster, my son gets scarred and walk's away from other kids way with scary body movements.
Question is: is this normal ? what should i do, to develop interaction skills with child. I do not have any relatives or any kids near by my place. We just started him sending to daycare.