Kuvult, your story is not clear
1) it seems that one should follow a (legitimate as Avira noted) minhag of the father even the father changed it. Otherwise, all chassidim should go back to minhag Ashkenaz …
2) when you are in shul, both of you should be doing the same thing – namely what is minhag of the shul you are in! If you wear T and the shul does not, ,you simply put it on at home. Not sure how it works other way around – I guess you wear it in shul and do not wear it at home 🙂