If you like longish books, here are some suggestions.
All-of-a-Kind Family by Sydney Taylor. Five sisters living on New York's Lower East Side in 1912 get a big surprise when their mother has a new baby.
Cougar by Helen V. Griffith. Is that really the ghost of a horse that Nickel sees?
Dog Friday by Hilary McKay. Who would have thought that a boy who's been attacked by a dog would actually hope that he could adopt the stray dog he found on the beach?
If you like fantasy and family stories, here are some other titles you might enjoy.
Among the Hidden by Margaret Peterson Haddix.
In a future where the Population Police enforce the law limiting a family to only two children, Luke has lived all his twelve years in isolation and fear on his family's farm, until another "third" convinces him that the government is wrong.
George Washington's Socks by Elvira Woodruff. In the midst of a backyard camp out, ten-year-old Matt and four other children find themselves transported back into the time of George Washington and the American Revolution, where they begin to live out American history firsthand and learn the sober realities of war.
Half Magic by Edward Eager. A magical coin grants the children half of whatever they wish for, with unexpected consequences.
Cracker! : The Best Dog in Vietnam by Cynthia Kadohata.
A young soldier in Vietnam bonds with his bomb-sniffing dog.
Storm Warriors by Elisa Carbone.
In 1895, after his mother's death, twelve-year-old Nathan moves with his father and grandfather to Pea Island off the coast of North Carolina, where he hopes to join the all-black crew at the nearby lifesaving station, despite his father's objections.
Crispin : The Cross of Lead by Avi.
Thanks for your request for a book match. If you're looking for a good series, here are some I'd recommend:
Thank you for your BookMatch request. I'm glad to hear you like Mary-Kate and Ashley books. Here are some other titles you may like:
Anastasia Krupnik by Lois Lowry
Anastasia's 10th year has some good things like falling in love and really getting to know her grandmother and some bad things like finding out about an impending baby brother.
The Steps by Rachel Cohn
Over Christmas vacation, Annabel goes from her home in Manhattan to visit her father, his new wife, and her half- and step-siblings in Sydney, Australia.