I bought my 20 month old a pair of the Payless ones. They are so tiny and adorable, and she walks really well in them, they stay on her feet. Everytime I put them on her she smiles and holds out her foot and goes "Ooooooohh! Pretty!" She especially loves the pink and purple tie dye ones.
I haven't seen real Crocs in such tiny sizes, but as fast as her feet grow, I'd rather spend half the money on the Payless ones anyway.