Is it true if you dream about somebody that means they were thinking about you when they were going to sleep?

or is this just a myth?Is it true if you dream about somebody that means they were thinking about you when they were going to sleep?
I have also heard that's what it means. However, maybe they were thinking about you at the same time as you were dreaming about them, and not when they were going to sleep. But, that's possible. I believe in that.