I am a US GC holder and I got married to a person who is having unexpired B1/B2 visa with 5 yrs multiple entry back in his home country. We have registered our marriage there. He has already traveled to USA few times on his current visa. We are not planning to get registered in USA and we want to keep his B1/B2 status as he needs to travel for his professional work. In this case when we enter USA, do either of us need to declare that we are married? Will it affect his entry? Thank you for your responses!