She went home and started asking Sakura a lot of questions, especially about her parent’s relationship. This is where Masashi Kishimoto got a bit meta on his readers. There are fans that find Sakura and Sasuke’s relationship unhealthy, and don’t ship them. Having read Naruto for years I know that Kishimoto likes to troll. The hint he added at the end — that Karin could be Salad’s actual mother — is just his way to get fans to talk.