He is taken in by Dong-soo (Gang Dong-won) who volunteers there but he then deletes the record. Dong-soo has an arrangement with Ha Sang-hyeon (Song Kang-ho) who spirits away unwanted babies for sale to rich couples who can't navigate Korea's byzantine adoption rules.
Meanwhile, two detectives watch on intending to follow and catch them in the act.
CW: nothing of note
You don't expect a movie about child trafficking to be a wholesome weird road trip but Hirokazu Kore-eda does this by So-young returning, being intercepted by Dong-soo and ending up wanting to interview the prospective parents.
The whole setup is somewhat contrived but you'll forgive it this.
It touches on what it means to be an orphan, what desperate people will do and finding companionship in unexpected places. You may sniffle, but also laugh.
Highly recommended 9/10.