Hello. We have 4 year old son. We were in US for 3. 5 years and recently came back. Due to pandemic and lack of Indian community there we were not social during our stay in US. My son's all development milestones were very normal except speech. He interacts very less compared to his age children. He follows all instruction. But interaction is very less. He is very active and started going to school too. Is it concerning that he is like late talker ? Do we need some special attention or we should allow some more time. Kindly help.