Paris and Nicole Up to Their Old Tricks?

Since settling down with the Madden twins, it seems like former besties Paris & Nicole have eschewed their former lifestyle to concentrate on family, work and charity.

But the Las Vegas Review Journal reports that this weekend, the girls, in town for a Good Charlotte performance at the Hard Rock pool, may have returned to their old ways!

In addition to an almost run-in with Paris' ex Stavros (who reportedly burned rubber as soon as he found out both he and Penji were in the same club), Nicole, who took a private jet with Harlow out to the bash (video below) reportedly got into a "catfight" at the valet station outside of the Hard Rock Hotel!

But I guess everyone's entitled to a little regression -- heck, it IS Vegas after all!