They probably came from a contribution you made somewhere in innocence on the internet and someone picked it up and put it on their site or public "tree" and did not source it. This has happened to me untold times and even found my father's photo on a stranger's website. I have taken to discretely including identification of the photo "From the Family Collection of . . . " placed in a way that it hopefully cannot be cropped off. Make it large enough but in much lighter background. Without sources you simply do not know if it is correct. This is a big problem today. Sadly, with all the hullabaloo about copyright, not much can be done once it's done. Also, it is appropriate to give the provenance - how did you get the photo, personal, handed down, through whom? I asked two people to remove it, one did the other didn't. Good Luck!
