Lesser is just a shorter name for Lesser Platinums.
The Platty Daddy is what happens when the het Daddy gene hits on a Lesser Platinum. The original Platty Daddy was imported by Ralph Davis. When he bred it, some of the babies looked normal (he figured out later that they carried the het platty gene), and some of the babies looked similar to the original snake, but they were a darker color. So he called them Lesser Platinums, which most people just call Lessers for short. He found that breeding a het platty to a Lesser or a Platty Daddy produces more Platty Daddys.
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