JL, it may surprise you that some
Heterosexual couple have anal sex
Hetereosesexual couples neglect their children
Heterosexual men/women sexually abuse their children or a close relative.
A great many of those abuses never come to light because children are frightened or no one will believe them.
Not everyone assumes the missionary position and has tea on the table at 6 o'clock. And what's more they never did but people kept secrets buried in families.