We've just adopted a 12 yo from elsewhere within the family. He knows DP very well and has known me for 4 years. In general, things are going really well, but he can be very rude and sulky. I don't think this behaviour was ever challenged before (he's been brought up by his gran since he was a baby and she has let him to what he likes).
Yesterday we had a family party, my dad said something to him (small group so everyone listening) about a mutual interest they share and DN completely blanked him, looked the other way, didn't answer. I was really embarrassed but didn't say anything at the time which of course I should have done. It happened last week with some of my friends and I said "DN, X is talking to you" which caused a massive strop and I didn't want to deal with that yesterday (was our DS first birthday).
But I am prepared to deal with it in an ongoing way. DP was fuming too. He does get very shy in public and I know this plays a role, but how much I don't know. He seemed to be able to answer other people without a problem.
I'm very new at parenting a 12 year old and would love some pointers on dealing with this sort of thing.