Na mahram doctor ke paas jaana

Q: Na mehrram ourat nurse, docter kisi na mehrram beemar mard ka ilaj cheack up ker sakti hai? Or aise hi na mehrramm mard docter kisi na mehrram ourat ka ilaj check up ker sakta hai? Or na mehrram school, college  tc ke teacher ko dekh sakte hain shewat ke ya baghair shewat ke?

Marrying the daughter of a woman one touched with lust

Q: A person has been married since 16 years and has three daughters( 14, 12, 7 yrs) and a son (3yrs). One or two year before marriage his mother in law was intimating him after that they( he and his mother in law) had sexual contact but not intercourse (dukhool). After the marriage they did not have that type of relation. Yesterday he heard from some source that her daughter was haram for him, so his marriage is not valid with her daughter. In that case children are also not halal with him and his wife. He loves his family very much. At the time of marriage he did not know her daughter will be haram for this action. He is very ashamed for his action since that time till now and asked forgiveness from Allah. Now he is very much worried about his wife and children. His wife did not know about that. We live here alone, where she will go. It will be very difficult for my daughters and son to survive with separated parents. My question is, his marriage is valid or not. If not what can he do to save six lives (any kuffara). May Allah reward you here and hereafter for helping his children, wife and himself. I will wait for your answer.