A childhood belief about virginity

I first heard the word virgin on the television, when I was about 9, and I asked my parents what that meant. My dad told me that it means that it was a person who had not slept with anyone. To confirm, I said that means you and mommy are not virgins and he said yes. I thought he meant slept together as in the same bed and thats it. For months until I found out what sex was, i thought me and my brother werent virgins because we used to nap on the same bed in the afternoon!