I second Little House on the Praire and All of a Kind Family. My daughter is reading through the All of a Kind Family series at the moment and she can’t get enough of it!
Although my 8yo is totally capable of and enjoys reading chapter books, he still enjoys good picture books during his free time too.
Frederick by Leo LionniStrega Nona and others by Tomie dePaolaThunder Cake and others by Patricia PolaccoThe Tale of Three Trees retold by Angela Elwell HuntWhere the Wild Things Are and others by Maurice SendakJumanji, Zathura, and others by Chris Van Allsburg
For chapter and longer books, he likes:
any of the series of Who Was … books (Who was Franklin Roosevelt? Who was Anne Frank?)The Boxcar Children by Gertrude Chandler Warner (only the first 19 books were written by Warner, so those are all he read)Number the Stars by Lois LowryThe Chronicles of Narnia by C.S. Lewis (if her reading level is good)
And, just so you don’t think these are “boy-ish” books, my 7 yo dd loves all of these too. You might also get yourself a copy of Honey for a Child’s Heart by Gladys Hunt. It is full of excellent book lists, categorized by age.