Wonderful News.. and a Question

On Tuesday, Locket went in for his check up... Bye-bye, infection! There was no trace of it! The vet says he thinks the reason it came back so badly this time was because his first round of antibiotics came when he was emaciated - four pounds on the vet's scale! - after I'd first brought him in. I have to continue the antibiotics for five more days and then he'll be done.

I also have a question about a behavior I've noticed in Locket and Buster that's really starting to disturb me. So it's warming up here and all the birds are back in the trees behind my house. Godiva, Cocoa, and D'Artagnan watch them, but not as much as Locket and Buster. Well, I came home from school both Monday and yesterday to find them so transfixed on the birds they didn't run to the door to see who it was. As I'm standing there watching them I hear this reallly funny noise: click-click-click-click, like a rattlesnake. When I look down at Locket, he's watching a squirrel intensely with his mouth open, clicking his teeth. I considered scolding him, but then he wasn't doing anything technically bad; he could have been trying to talk, for all I knew. I came back a half-hour later to Buster clicking just like Locket had, only at a big, fat bird. What is this? Is this aggression? I asked Cassie if her cat Dixie Hiccup does this and she said no, so I am completely in the dark. If any beans or furbabies could help me understand this, I would really appreciate it.

-L