Molly & Platy Cross?

[Kalinkacat]

So I was transferring my Mollies and Platys from the basement to the main tank this week.  Nothing was in that basement tank except for Platinum White Sailfin Mollies, Green Sailfin Mollies and Sunset Platys.  Not even any cleaner fish - just them.

Looking at the fish I just transferred today, I notice several of them - so far just the young greens, non of the whites (I have no adults left) are green with platy-like red on their bodies, not the fins but along their bodies.  Not disease, colouration.  I will try and get pictures but isn't it suppose to be impossible for Platys and Mollys to breed?  That's why I kept them together so I wouldn't cross with my Chocolate Mollies.

Thoughts?  Like I said, I will try to get pictures but they are really pretty.

Sorry about pictures and algae on glass but it should give an idea of what they look like, although their base colour is green not white.  If it's not a cross, how did they get the platy orange/red on them?