Yes, and the propensity of humans to nurture small cute baby animals (if they didn’t eat them). I think it’s quite likely that on occasion young wolves were found minus parents and brought back as entertainment to the hearth. At some point, some of them were useful as adults for keeping away other animals, cleaning up refuse, etc and a partnership was born. Dog society is similar to human society, so they fit well.
At least my dog says so.
The only problem with that is that I think the whole pack would have to have been eliminated. While the parents might have died, it’s a fat chance the whole pack would have been lost and I think the pack might take responsibility for its pups, even if they’re not offspring of any left.