It's also because Jing Xin hasn't officially acknowledged his relationship with the Nangong family yet. Otherwise, Fang Xiu could directly go to the Nangong family to help find her sister-in-law, but currently, she doesn't live with the Nangongs, so it's inconvenient for her to go.
Before knowing that Nangong Beiying was her sister-in-law, Fang Xiu didn't think much of it. Now that she knows, she still doesn't feel much, because she understands that for a woman to live happily, her partner must be someone who can be caring; otherwise, the woman's life as a wife would be too painful.
She knows Xiao Qi is a good man, so she hasn't said anything about it. But Jing Xin is somewhat dissatisfied. A sister who has just been reunited with the family is about to be taken away, which would make anyone feel uncomfortable.