Connection between Candy's dog and Lennie

In part 5, of Mice of Men by John Steinbeck a traumatic scene happened. First off I would like to point  out that the reason John Steinbeck may have chosen to have Lennie to get killed was because he was most people's favorite character, which made the scene way more dramatic. I have noticed throughout the book that Lennie has been symbolized as an animal, not a human. My connection to this is that Lennie really symbolizes Candy's dog (minus the old age) in the sense that he is useless and has no point of life. I also believe in this connection because George wanted to be the one to kill him, just like how Candy wishes that he is the one that killed his own dog. I realized that even though George actually was the one to kill Lennie, he was really looking out for him. He wanted to make sure that Curly was not going to kill him, and make him all scared. I also feel that Lennie trusted George, "I've knew George since-I forget when-and he ain't never raised his han' to me with a stick" (102.) This shows that Lennie put all his trust in George and would never do anything that would put him in more danger, so I feel that George killed him to protect him from more pain than he gave him.