The mysterious odor

Today the family was plagued by a mysterious, pungent and frankly disgusting odor.

Paul and I first noticed it in the morning as we were reading the paper and having our coffee.

Paul: Holy cow! What is that smell?

Me: I don't smell it.

pause

Me: Ohhhh! Wowwww.... Okay. I smell it.

Paul: Ethan! Go and change your shirt - it's the same one you wore last night to bed.

Ethan: I don't smell! It doesn't smell! (He sniffs his own shirt). See? I smell good!

I notice that he is actually wearing exactly what he was wearing yesterday. God only knows if he even bothered to change his underwear.

Me: Ethan - go and change everything. Shirt, pants, undies, socks.

Ethan: Fiiiiine.

He stomps off.

Later, I am in my room typing and Zayd comes in to talk to me. All is well... and then Ethan comes in again.
About two minutes later and the smell hits again. And this time it is REALLY bad.

Me: Ethan! Did you change?

I look him over. No. He did not.

Me: Ethan, go and change or you are not going Christmas shopping with us. Come here...

I take a whiff of him. Hmmmm.. I don't notice anything in particular.

Me: Zayd is that you?

Zayd: Maybe.

Me: Well - for God's sake... go take care of that.

Zayd: Okay.

Zayd decides to take a shower. Afterwards he comes back in to my room. I take a sniff - all seems good.

Ethan comes in again. This time with a new shirt, but the same pants. It takes about two minutes again.. and the smell hits.

What. The. Hell.

Me: Ethan. You need to soak in the tub too.

We get Ethan in the tub. Finally everyone is clean, showered, soaped, and fresh. We head out to shop.
A few hours later when we return home... Zayd, Ethan and I go to my office in the basement to wrap gifts. Zayd is sitting next to me and I smell the smell again. This time, it isn't quite a potent. But the closest thing I can figure is it is his tennis shoes.

Me: Oh my God Zayd. It's your shoes. They smell awful. We need to get rid of those.

We get our gifts wrapped and under the tree... the boys start raiding the kitchen and then the smell overtakes all of us.

Zach: WHAT is that! THAT is sick!

Ethan: WHOA...

Evan: It's ZAYD!

Me: Zayd... come here.

He is walking around in his socks. As he approaches, it becomes obvious that indeed it is his feet. The grossest smelling feet I have ever smelled.

Me: Zayd. Take off those socks, take them to the laundry room and wash your feet.

Zayd: It's not my feet. They don't smell.

He takes his socks off in front of me and smells his own feet. Now, without his socks on... I think I'm going to pass out.

Everyone: Ohhhh!

Zayd: Oh. Yeah. It's my feet.

He disappears for a while and returns.

Zayd: Do my feet smell now?

I cautiously lean towards his feet - but not too close.

Me: No. They smell fine now. Thank you.

Zach: Where did you wash your feet?

Zayd: The bathroom sink.

Everyone: Ohhhh! Ewwww!