Thank you for this interesting ask! I hope you don’t mind this simple, goofy response to it.
Fun facts: In the first panel, Softboy is singing and dancing to a snippet of the song “When You Had Left Our Pirate Fold” from the Gilbert and Sullivan operetta The Pirates of Penzance, in which the protagonist was also born on Leap Day.
The reason why only Softboy and Leo have birthdays is, honestly, because they’re Chris’s two favorite toys. He simply didn’t find the time or good reason to choose special birthdays for each individual toy in Chrisville. However, this simply means Chris decided to celebrate them all on “Chrisville Appreciation Day,” the date of which has yet to be determined.
Also, I should note that while Softboy was handmade, his “birthday” has no relation to when he was finished being sewn together, nor does it necessarily reflect when he first came to Chrisville. This date was purely chosen for the reasons listed in the third panel.
One small note on Leo’s reaction to reading about his zodiac sign; Leo doesn’t like the idea of zodiac signs controlling people’s lives, influencing relationships and self-worth with possible nonsense. To be entirely honest, Leo fits the general description of Leos, but he can’t stand the suggestion that “the stars” know him better than he does.
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