Using the immigration bureau's online platform, Xu Huo made contact with private detectives near the two families' residences, commissioning them to investigate the families' pasts.
The doctor that appeared at Seventeenth Hospital didn't start by taking several children away. Their deaths all occurred after some period of "growth," so it was clear that the "doctor" wasn't just focused on one or a few "seedlings"; he was casting a wide net.
Shang Shuming might also have been one of the fish in the net. As for whether the person who later appeared before Peng Ya and the others was the real "Doctor Shang," that wasn't certain.