How do little kids learn and remember their parents' names?

Stupidest question of all, I know...I'm talking about 3 and 4 year olds. Do the parents have to remind the kid what their names are? I mean, usually kids just use "mom" "dad" or some variation, and the parents refer to themselves as mom and dad. So how do they remember the names? And do the parents have to sit the kid down and tell them, "your mom's name is..." or "Do you remember my name?"