In Texas, in the 1800s, a boy named Travis, another named Little Arliss, Mama and Papa all live in a cabin. Papa needs to go out into the country and leave them for something, so he leaves Travis as the one in charge.
Travis is doing a great job. However, he finds an ugly old yeller dog stealing their food. Travis was going to shoot the dog, but Little Arliss had a fit, and convinced Mama to keep the dog.
Little Arliss gets in trouble with a bear, but Old Yeller protects him! Travis is thinking differently about Old Yeller now. Maybe he isn't so bad
Travis is marking hogs, when he falls and gets hurt! Luckily, Old Yeller comes in and saves Travis, but he gets badly hurt.
Old Yeller is getting better, and so is Travis. However, hydrophobia is spreading, and Old Yeller gets hydrophobia. Travis has no choice but to kill Old Yeller.
Travis is sad, but is accepting of Old Yeller's death. The family gets a puppy so they're not lonely.