your motherinlaw seems to be a jealousy. Takarada-monami

He lost his husband for several years. After that, her daughter got married and Monami felt she had a lot of shoulder loads. His daughter and wife were also close, so he thought it was time for him to be his grandson. However, Monami is unaware of the sound of his daughter's jealousy that she hears leaking like every night and dirtys her inner underwear. And Monami was so worried about how good her niece's son-in-law was, that she secretly looked at the work of her daughter and wife and became complacent.