Sperm and Hard-boiled eggs

So, this morning I made Em hard-boiled eggs for breakfast. The following conversation ensued:

Em: Look, Mom! A perfect yolk...I didn't break it while I was opening my egg. Maybe I should take it to Show and Tell...

Me: As soon as we put it in a bag it may break...

Em: Mom, was this a boy or a girl chick?

Me: Neither. It wasn't fertilized so it was just an egg.

Em: Yeah, but there's a yolk. I killed a baby chick.

Me: No, Sweetie, you didn't kill a baby chick. All eggs have yolks, they are the sac that holds the baby chick if it were a fertilized egg.

Em: (Thinking...)

Me: Em, do you remember when we talked about eggs and fertilization? Well, an egg needs to be fertilized by a rooster in order to become a chick.

Em: How does it become a boy or a girl?

Me: Well, some sperm are male and some are female, so when the male fertilizes the egg with his sperm, depending on which one gets there first, that's what kind of chick it is. It's like a race, the first sperm there wins and gets to decide if it's a boy or a girl.

Em: (Thinking...) So, Daddy knows what kind of baby is in your belly?

Me: No. Nope...huh uh...when a male fertilizes an egg there are literally millions of little sperm that swim really fast to try to get to the egg first, and that's just too many to count to know which is which...(Help me out here, people! Losing it, here!)

Em: (Thinking...) So, wow. Huh. (Inquisitive look spreads across face) So, it took a really long time for daddy's sperm to make the baby in your belly now...I mean from when Noah was born until now...

Me: (Heading toward bathroom, looking for my out...) What? Huh? Oh...uh, yeah...uh huh, yeah...um, run and get your coat on, kid, Mommy's going to go potty really fast...meet you in the car...

Seriously?! All I did was boil up some eggs...Dear God, help me, please, when this conversation introduces the whole concept that eggs and sperm aren't always given the opportunity to "make contact".