A woman’s ablution is not invalidated by touching a child’s private parts

Does a child have private parts?Meaning: If a woman touches a child’s private parts, is her ablution invalidated?
A woman’s ablution is not invalidated if she washes her child and touches his penis or private parts; because that does not invalidate the ablution. Even if a man touches his own penis, it does not invalidate the ablution unless it is done with sexual desire. If it is done without sexual desire, it is recommended to perform ablution, but it is not obligatory.