The magic school bus chapter books have the text broken up by the kid's writing. Geronimo Stilton didn't really work here and to be honest I thought they had an odd tone for children's books.

Ive just been thru this with my ds who's now 4.5. He's still not keen on reading chapter books to himself and is in a phase of wanting me to read to him everything (i can sometimes get him to read page for page with me but that's about it).

We did Henry & Mudge, Nate the Great (olivia sharp is his girl counterpart), Geronimo Stilton, Tashi. He also has read some picture books. Seuss books are good as they're looooooong but not many sentences on a page usually. Eric Carle books are also good. I dont know if they're available in the US but here in Australia we have Solo readers/chapter books which are about the same level as Henry & Mudge. Zac Power also has some easy chapter books.

I would echo what polarbear said above. Just let her pick books and she'll discover some great ones and some not so great ones. The Little Bear books are adorable and have oodles of illustrations with decent vocab and some repetition, too. Letting her discover books plus continuation of read alouds will do wonders.

Also, the book Some of My Best Friends Are Books has great tips. That and the Read Aloud Handbook by Jim Trelease.

I hate to suggest them, but many girl early readers devour the Rainbow Fairies series.

Ultramarina, DS also devoured the Rainbow Fairies book when he was about six. He was already reading past that level but they really appealed to him, for some unknown reason. Although, now that I think about it, the idea of fairies is pretty timeless. lol

How about "Amanda and Her Alligator" by Mo Willems.

It is picture chapter book ... with 6 1/2 chapters ...

Cynthia Rylant's Mr. Putter and Tabby books are also "picture chapter books" with 4-6 chapters. I just love this series; it's so rare to have children's books that center on the elderly.

I remember that at that age, my DS jumped to the Magic Tree House series. All the black and white print with tons of words scared him - so I got him the ebooks and showed him how to zoom in to make the words bigger so that there were fewer lines per page and he was off to a great start. He still re-reads those books at age 7 because he loves that series a lot.

I think the RF books work well for some young kids because they are very predictable. That may also help with fluency. Their rated reading level is surprisingly high, btw--I don't think it's accurate.