What Did You Say?

Asher: I've said it a million times.  What are you death?
Liam: Death?
Asher:Yeah, are you death?
Liam: It's dead.
Asher:No, it isn't.
Me: No, it's deaf.  With an f.
Both: (Blank stares)
Me: If you can't hear then you are deaf.  D-E-A-F. 
Both: oh.