Molly’s Family by Nancy Garden

While preparing decorations for Open School Night, Molly and several of her classmates draw pictures of their families and discover that family means something different to each of them.
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In preparation for her kindergarten class's Open School Night, Molly and her friends draw pictures of their families. Molly draws herself, her two mommies, and her puppy. But Tommy tells her she can't have two mommies—and Molly decides she doesn't want her picture to be displayed. Eventually, though, she finds out people have many different kinds of families, and she lets her picture be put up with all the others.