The great comedian W.C. Fields once famously said, "Never work with children or animals." But come on -- sometimes animals are really cute! Oh, and we guess children aren't so bad either. We kid, we kid ...

Whether you need a prematurely precocious tyke to spout one-liners, or a serious little man to play the heir to a lineage of serial killers, it's not the kind of thing you can just CGI in. To tell a real-life story, you're just gonna have to suck it up, work on your knock-knock jokes and get ready to act alongside real-life little ones.

Fall TV is chock full of children, but there are a few special squirts -- and several more mature minors -- that have caught our eye, including a new little Lily on 'Modern Family,' a hot 'Terra Nova' teen and an animated 40-year-old trapped in a 7-year-old's body.

Check out our favorite kids of the fall TV season after the jump ...