You know... I'm thinking to the courses I've just taken in Photography and related things. It covered basic legal issues such as copyright and how it applies to photographers. You don't have to be commercial and a 5 year old with a Walmart digital toy has the same technical protections as the Wedding photographer using his $7k cameras.
If the girls took those photographs, they own those photographs and nothing changes that. It's automatic copyright and well established precedent and
law. Suing the site, if it's based in the US, would be a slam dunk and easy shot given the obvious and outrageous copyright violation. It's
precisely the same thing copyrights are sued over all the time. The photo issue just happens to be all but cut and dry when proof of origin is so
clear and unquestionable.
Just my two cents...and not legal advice or anything