Ellie
Ellie is a female Woolly Mammoth, who Manny, Diego and Sid meet on their migration to escape the flood in Ice Age: The Meltdown.
It was revealed that when Ellie was young, she was separated from her herd during the age ice age. She came across two opossums named Crash and Eddie, along with their mother. She later forgot her origins and thought that she was an opossum.
Manfred met her when he was afraid that he truly was the last mammoth, and he was overjoyed that he had found another of his kind, but got a surprise when he saw that Ellie believed that she was an opossum. Nevertheless, he and his herd (or rather, Sid) welcomed Ellie and her brothers to travel with them. During this time, Ellie displayed the mannerisms pertaining to an opossum as well as insisting (despite obvious proof that she was not a possum) and this was weighing heavily on Manfred's patience, namely when she claimed that the act of bravery that he had done of fighting off the sea reptile Cretaceous was dumb.
Soon, Manfred got his time to be alone with Ellie when he and Ellie went for a walk through a wooded area, where Ellie had a flashback that told her of her past. Upon remembering this, she knew that she was a mammoth, but was soon angered at Manfred for implying that they must mate in order to save the mammoths from extinction, but in time, she apologized for over-reacting. She and Manfred also slowly fall in love now and the next morning when they resumed travel, this affinity did not seem to end.
Soon, however, this new "herd" reached a horrible obstacle between them and safety from the oncoming flood: a field of geysers, which Manfred explained must be crossed, but Ellie would not listen: she and her brothers felt that they must go around. But this proved to be disastrous: as they were trying to reach their destination, some rocks caved down and nearly crushed Ellie and her brothers, but trapped them instead in a sort of cave. Manfred rescued Ellie, for the water was flooding into the cave where she was trapped and had nearly drowned Ellie. She and Manfred escaped and regrouped with the others, but faced another problem, for the waters were still rising.
Eventually, however, the waters subsided and to top it all off, a herd of mammoths made their way into the valley. Manfred thought that because the mammoths had come, that Ellie would not want to remain with him. Manfred was persuaded otherwise by Sid and Diego and soon caught up with Ellie and confessed his feelings, saying that he wanted to be together not because they had to be, but because he himself wanted to. Ellie accepts him as her mate. The mammoths trumpet while Manny and Ellie embrace. Manfred and Ellie decide to become stay with their old friends, taking along Sid, Diego, and the possum brothers.
In Ice Age: Dawn of the Dinosaurs, she and Manny are married Ellie is pregnant with their first child. When they find the Dinosaur World under their feet, they have to go in and search for Sid in Lava Falls. When very close to Lava Falls, Ellie falls into labor,and gives birth to Peaches (which was the codeword for if Ellie went into labor on the trip). When they return to the surface, Ellie introduces Peaches to her new home.