All Animation Is Disney: Besides being mistaken for a Disney movie, it is also sometimes mistaken for a Don Bluth movie, which it isn't. Its posters and trailers which proudly proclaimed "from the creator of An American Tail" would have you think otherwise.
In a literal invocation of All Animation is Disney, 20th Century Fox would end up being bought by Disney, resulting in Disney technically owning the film despite having nothing to do with it.
The movie's full of beautiful James Horner scores. "The Forest" is a prime example.
Big-Lipped Alligator Moment: The part where the group comes across the flock of birds, and has to save a young bird named Bosworth, whos stuck in a mud puddle. This section really doesn't contribute anything to the story, except comic relief and to introduce the concept of "the Yellow Dragons."
Michelle, definitely. Losing your parents and being poisoned by toxic gas will make that to you.
Cornelius certainly qualifies. He and his younger sister lost their parents when they were still kids, and then he loses his sister at the beginning of the movie. Especially given that now Michelle is all the family he has left in the world, and he can only sit there helplessly as she's slowly slipping away.
Also Abigail, when she starts feeling bad about herself for thoughtlessly leading the furlings into danger.
Edgar also has his moments of this.
Also Bosworth, the young wren trapped in the mud that the furlings save.