Yes, you would be probably misunderstood if you said your sentences. It sounds as if you slept with them in the same bed, not necessarily having sex, though.
Here are some corrections of your sentences:
'....referring to someone having (not has) sex.....'
'I remember that my Mom, Dad, and I (not me) shared one bedroom.'
'I had my own little bed....or a crib perhaps? (a bed for babies).
'My parents and I (not me) slept together....'
Originally Posted by blacknomi