I took a picture of this bikini at a children’s clothing store in L.A. It is size 12-18 months:

NEW! (May ’10): Reagan B., Tara C., and Ma. Elí C.L. told us about a children’s bikini for sale at the chain Primark in the U.K. The bikini came complete with a top sufficiently padded to make girls look as though they have breasts:

The chain quickly pulled the bikinis after a public outcry about the sexualization of children.

NEW! (July ’10): Naomi sent us a link to Babi-kini, a website that sells string bikinis for little girls. Not only is the girl on the homepage in a bikini, but she’s in a typical swimsuit-model pose, too:

They sell a variety of styles, including one similar to the zebra-print one I originally posted above.

I went to the “one-piece swimsuits” section, but an error message came up saying there were no items matching my search. Sigh.