From WENN.com

The star of the upcoming The Amazing Spider-Man has revealed his character Diego was supposed to die in the first Ice Age movie - but kids were so upset at early screenings Leary's wild man lived on for the sequels.

He tells WENN, ""Diego is supposed to die and I said, 'This is not gonna work; you can't kill a major character, kids bum out.' So they screened it the first time and kids bummed out.""