Spike is a deep violet ostrich with a pale pink neck. His legs are darker pink in color, with his beak being bright orange, while his eyes are black. The text describes his head as being speckled, but this is not correctly pictured.
Spike is an oblivious infant with a knack for getting in trouble. Despite this, he does his best to learn, and always follows the instructions of his adopted father, Pumbaa.
While searching for grubs, Pumbaa comes across a peculiar white object. Mistaking it for a stone, he starts to kick it toward Simba, but the lion cub stops him just in time, explaining that the object is in fact an egg. Timon comes up to join his friends, and the three muse as to what kind of animal could be inside the egg. The three agree to go fetch breakfast, and Timon leaves the egg in a patch of sunlight atop a tree stump.
However, Pumbaa's thoughts keep drifting back to the egg as he hunts, and he eventually abandons breakfast in order to keep the egg safe from potential predators. When Simba and Timon return to the tree stump, they find Pumbaa perched atop the egg like a mother bird. No sooner have the friends reunited when the egg hatches into a newborn ostrich chick, who mistakenly refers to Pumbaa as his mother.
As the ostrich chick attempts to take his first step, Pumbaa steadies him and warns him to be careful, much to the amusement of his friends. They are sent even further into hysterics when Pumbaa refers to himself as "Mummy Pumbaa" and leads his newfound son, Spike, to an ant mound. Spike watches Pumbaa take a bite and attempts to eat just as much, but he ends up spluttering on too much food, and Pumbaa urges him to take smaller bites.
After Spike's first meal, Pumbaa leads the way to a mud hole, with Spike hitching a ride with Simba. Once they arrive, Pumbaa jumps right in, and Spike moves to follow, but he soon gets trapped in the oozing mud. Simba is quick to pull him out, though Pumbaa reacts in confusion, unsure as to what all the fuss is about. Nevertheless, he comes with Simba and Timon as they lead Spike to the river and wash him off.
After Spike's bath, the four friends collapse in a heap and fall into a deep sleep. In the middle of their nap, Pumbaa is awoken by Spike, who insists that he's still hungry, but Pumbaa grumpily tells the little ostrich to leave him alone. He then flops back over and falls asleep once more. The friends continue to sleep, but when they wake up, Spike is nowhere to be found.
Immediately, the three set out in search of Spike. As they look, Pumbaa begins to cry, worrying that Spike will be made into lunch by a hungry predator. Soon after this, they hear a faint singing voice in the distance and follow it to where Spike is stuck in a thorny bush. Timon volunteers to help the chick out, and Pumbaa greets his adopted son with relief. Spike merely curls up in Pumbaa's mane and falls asleep.
The next morning, Pumbaa attempts to teach Spike how to hunt and dance, but Spike is no good at activities more suited to warthogs. Despite this, Pumbaa keeps encouraging him. However, he admits his misgivings to his friends, worrying that Spike doesn't realize that he's a bird. The three then agree to find him a real ostrich family so that he doesn't grow up not knowing how to behave like a bird.
The friends set out for the place where they'd found Spike's egg, and they encounter a family of ostriches, who recognize Spike as their long-lost son and brother. Spike's mother thanks the trio profusely, and they go on their way, with Spike staying behind with his family. As the three walk away, Pumbaa is happy that Spike has found his real family, but he still feels like he's going to miss being called "Mummy."
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