Could someone sue you if you had their photo on your website?

like if someone found their photo on awkwardfamilyphotos.com/peopleofwalmart or another site where they post funny pics of people could you actually get in legal trouble?

Watermark it if it isn't already and say they stole it from your site, otherwise give credit where credit is due, and either post a link instead of the pic, or at least provide information about the source.