Daily Easter Egg #19: Princess Toadstool's ???, Super Mario RPG

What is she hiding?

So, here I am again with yet another Super Mario RPG easter egg to share with you all! Speaking of sharing, Princess Toadstool (Peach) isn't willing to share her secrets with the player. 

If the player pokes around in Peach's room and finds her ??? before she joins the party, her grandma will try to bribe the player to keep quiet about it. The ??? is located in the back of her room between the fireplace and the chair. If the player finds the object when Peach is a part of the party, she will scold the player for being too nosy and not respecting her privacy. So, what is this hidden item Peach wants to keep a secret? I'll let everyone in the comments speculate as to what this item's mysterious identity is. 

(Source)