What I remember about the story is that sakura and kakashi have sex and sakura becomes pregnant. She goes to tell him to only see him with a woman. Sakura sort of flees Konoha goes to Suna I believe. The only people who know are tsunade and shizune. Fast forward, their child looks exactly like Kakashi. He doesn't suspect the boy is his. Tsunade puts them on a missions posing as a family. I will be forever grateful if someone can find it! :)