This is Calvin's new funny joke:

Calvin: Hi, Mom.  (Comes over, chats about something, gives me a big hug.)

Me: (Thinking -- how sweet!  He still wants to hug his mom!)

Calvin: (Leans over during the hug and blows a raspberry on my arm -- we call it a Zerbert.  Runs away laughing.)

And I fall for the "I Just Want To Hug Mom" routine every time.  You'd think after this happens repeatedly over the past few days that I'd remember and suspect the Zerbert.

Nope.  Here's me, still thinking he wants to hug his Mom.

And then comes that big wet BLURGH on my arm.