To create interesting characters, think about their relationships. The human baby could have a special bond with a particular animal, say a baby mammoth. They grow up together, learning from each other. The baby's parents could be strong and resourceful characters. The father could be a great hunter, and the mother could be very knowledgeable about medicinal plants in the Ice Age. These traits would not only make them interesting but also drive the story forward in terms of protecting the baby.
For the human baby, you can give it distinct features like a curious nature. Maybe it has big, bright eyes that seem to hold a lot of wonder. For the animal characters, like the sloth Sid, you could make them have their own quirks. For example, a woolly rhino could be really clumsy but with a heart of gold, always accidentally causing a bit of chaos but meaning well when it comes to protecting the baby.
To create an interesting Ice Age Continental Drift OC fanfiction, you need to consider the setting carefully. The changing continents, the new environments, and the challenges they bring are important elements. Your OC could be a solution - finder. Say, an OC who discovers a new route for the animals to migrate safely during the chaos of the continental drift. Also, develop relationships between your OC and the canon characters. A love - hate relationship between your OC and Diego could add a lot of drama to the story.
Maybe the human baby is a special child with some kind of unique ability. In the Ice Age setting, this ability could be related to communicating with animals. So the baby uses this power to bring different animal species together to form an alliance against a common threat, like a large flood or a group of extremely aggressive and territorial creatures.
In an 'Ice Age Baby Dinos' fanfiction, the main characters could also include the Ice Age animals that interact with the baby dinos. For example, a woolly mammoth who befriends a baby dino and helps it navigate the frozen world. Also, there might be a sly saber - toothed cat that at first seems like a threat but later becomes an ally.
The baby Moeritherium might adapt by growing a thicker coat of fur. This would help it to stay warm in the frigid Ice Age temperatures. It could also learn to follow the migrations of other animals to find food sources that are still available during the cold period.
One idea could be a story about a human from the Ice Age who discovers a hidden cave filled with ancient markings that lead to a secret power. Another could be a love story between two humans from different tribes during the Ice Age. Or perhaps a story of a human's journey to find a rare herb that can cure a deadly disease spreading in his tribe.
To make Ice Age human characters more believable, give them skills relevant to the time period. For example, they should be good at making fire, hunting, and building shelters. Also, their language should be simple and basic, as they didn't have complex grammar systems back then.
In some fanfictions, baby could develop from being a carefree little creature to a more responsible one. Maybe he starts to look out for peaches more. For example, when they are in danger, he takes the lead to protect her.
To develop characters in Ice Age OC fanfiction, start with their goals. What do they want to achieve? Is it to find a warmer place to live or to make new friends? Their goals will drive their actions in the story. Also, think about their relationships with other characters. Do they have a rival? Or are they in love with one of the existing characters? Another important aspect is their flaws. No one is perfect, so your OC could be clumsy or have a short temper. These flaws will make them more relatable.
One idea could be that Diego and Shira are transformed into humans by some magical force in the Ice Age world. They then have to learn how to live as humans while still retaining some of their animal instincts. For example, they might be really good at hunting in the wild as humans because of their past as saber - toothed tigers.
As humans, Diego and Shira could have a more nuanced relationship. They might experience jealousy in a new way. Say, if another human showed interest in Shira, Diego would have to deal with his feelings in a different manner than he did as an animal. Also, they could express their love more openly, like through hugs and kisses, which are more typical human ways of showing affection.