[nemothekid]

>Yet the father was the one being fished.

Not sure I understand. The father's phone was stolen, and the son was contacted, and the son logged into the account.

>How?

Anyone can pop out the sim card and plug it into any dumbphone, navigate to settings and read the phone number. I assume there's probably a USB device to dump data on a sim card.

>Losing it is not the same as having it stolen, though.

Your phone is lost until you attain the information that it was stolen. I fail to find it now, but there was a tiktok of a woman who lost their iphone at festival and it turned up in china where she also was unsuccessfully phished.