My two-year old loves "Jack and Jill's Treehouse". There's something about treehouses and cabins that he likes lately. The structure of this story is similar to the song "The Rattin' Bog" from Sharon, Lois and Bram, and the French-language folk song "L'arbre est dans ses feuilles". There's also a small rebus-type drawing with each element of the story (i.e., branch, wood, floor). For these reasons my two-year old is able to "help" me read key words in the story (after reading it together a bunch of times).