Forum:Harpie Lady Effect vs Rules

Howdy,

I was recently playing with my Wind/Harpie deck when I pulled all three harpie ladies plus Harpie Queen. I have more than one of each of the Harpie Lady cards 1-3 and I wanted to double check on something. Since the card name says Harpie Lady I, Harpie Lady II, Harpie Lady III and Harpy Queen, then the effect says, "This cards name is treated as 'Harpy Lady'", my question is then this: Is it illegal to have more than one of each card that has this effect or since this effect says "Treated as" and not "Changed to" does this rule not apply to these cards?

I would be very happy to know the answer either way. Thanks Much!