has anyone not heard their dog bark?

Baira barks all the time but we've had Leos almost a year now and I don't think i've heard him bark once. I've heard him play growl whilst he's playing but he doesn't bark.......ever.

Binni is 10 months old and VERY rarely barks.  She was 6 months old when she barked for the first time. I think she scared herself when she barked.  It really concerned me when she was little, but we are used to it now.  Binni is however, very vocal. She loves to sing.  It's a very high pitched yelp almost.  If I leave the house, you can hear her "singing" until I come back in. 

I have a 7 month old english springer spaniel that barks if the grass blows in the wind.  So, I will not complain about Binni not barking. 

I'm with you everbell.  Dutch is the worst.  He barks at other dogs barking, the doorbell, and if a motorcycle goes by (He thinks it's my son).  He also barks at barking dogs and doorbells on TV.  When Reilly barks, I go check it out, he usually has a good reason.