The short answer is that fanpop provides an "image credit" field which every user should use to make it clear that no ownership au rights to the picha are implied kwa being ilitumwa here: the picha still belong to <these people> (what wewe insert in the image credit field).
Do a tafuta of fanpop (or just participate in a foramu long enough) and wewe will quickly find dozens of pages of people discussing how to properly use the image credit field. One fairly straightforward method is described in this article:
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