Too many writers have approached too many agents and editors with pitches like: my daughter and her friends love the book and so does my mother, or my son's teacher read it to her class and they loved it. Then the ms turns out to be sub par. People who have a personal connection to you are not usually reliable beta readers. As Debbie said, children can give you insights, but don't use them as references.
Sometimes someone with a close personal connection can be helpful, but often not. I have six children. I only use one of them as a beta reader, but I wouldn't use her as a reference in a query. The one child I use is trained, understands what I'm looking for, and follows directions. For example, I might ask, "Is there too much romance or not enough?" or "Does the sidekick take too much attention away from the MC?" She gives me valuable feedback, but it's not relevant in a query.