Miku Ikuta - My daughter-in-law

My stepson's wife, Miku, who lives with us, suddenly became very upset and asked me for advice about my stepson's affair. When I asked her about it, she said that her stepson was not answering the phone and was trying to cover it up. I tried to quiet her down, but her anger didn't seem to go away. I'm going to have an affair too! My father-in-law took pity on his daughter-in-law, and what did he do?