De-Aging Potion

[lilah80]

This is driving me mad. This was a fic in which there's a potions accident and Snape and Lupin are de-aged into toddlers. Snape, being a very demanding toddler, is being cared for by Madame Pomfrey, and Sirius ends up taking care of Baby Remus. I'm pretty sure that James tries to use Baby Remus to pick up girls, which horrifies Sirius. The full moon comes, and they have to deal with Baby Remus' transformation, which was pretty heart-breaking. I think that the de-aging potion wears off at the end of the transformation.

I know what you might be thinking, but this isn't Second Childhood from Azkaban's Lair. Totally different fic. Please help!

FOUND! It was escribo's When I Grow Up.