My eldest son has just turned 12/ he used to be quite chatty but now he doesn't talk very much. Now that it's half term he doesn't want to go to the park and play with his siblings/friends/ When I talk to him, I often have to repeat what I said to get an answer. All he does is to read on the sofa or play a bit on the computer (he has a limited screen time).He doesn't take any initiatives to organise something with his friends. I don't think he has any problems at school. He is in year 7 and went from a local relaxed primary school to quite a strict and academic school, but he copes well. Is it a typical thing for this age or should I be worried?