"We won't forget about you"
- The entire premise: It doesn't even cross Sid's mind to abandon Roshan (which makes sense considering he knows how awful it feels to be abandoned) and he pulls Manny and Diego along for the trek to get him back to his father, and along the way they come to love the baby and they become a family of their own.
- The baby's name is Roshan, which means "light" or "light at dawn" in Hindi, alluding to the fact that he's the one who brings light to the three very lonely main characters on a very deep level.
- Frank working a minor offscreen miracle to surprise Carl with fresh greens and the last dandelion of the season — and literally wriggling with happiness as the latter gushes over it. Considering they're best remembered as "the gay rhinos" and spend most of their screen time trying to break Sid's neck, it's sweet that the first we ever see of them is a happy moment establishing how much they adore each other.
- Mama Bear Nadia using the last of her strength to push her baby towards Manny. Who uses his trunk to help her.
- Sid's relief on seeing that Roshan is okay after being in the water. He's then the one who insists that they need to take him back to his people. It's implied that on top of just being a sweet sloth, Sid is so adamant because he knows what it's like to be abandoned.
- While they're alone, Manny tells Roshan that he's not gonna be a very good predator as a human, belittling his lack of fangs and claws and wondering what's so special about humans, before the baby gives him a warm hug and Manny is speechless.
- After the ice slide, Diego thinks that Manny and Sid are his buddies enough to give Manny an affectionate punch on the arm and excitedly ask them if they're "up for round two".
- "That's what you do in a herd." What makes the line truly heartwarming is that when Manny first says it after saving Diego, he says it nonchalantly, as if looking out for others was simply animal nature.
- The scene in the cave. While Manny is thinking of the loss of his child, Roshan puts his hand on the drawing. Then Manny scoops him up and he hugs him with his trunk as tears well up in his eyes, not just because he loves the baby but because he's made the decision to let go of his hatred of humans.
- Even Diego is touched by the cave scene. This gives Diego second thoughts on his mission to allow Soto to kill the baby as well as Sid and Manny.
- A minor one during the campfire scene. After Diego puts out the flame on Sid’s tail, he at first playfully threatens him, then admits he’s kidding and gives him a noogie. The Diego at the beginning of the movie would never do this.
- Not long after, Sid talking about how Manny may act like a jerk, but is just a softie, admitting he really is grateful for Manny saving him. He doesn’t just see the mammoth as a body guard like the latter thought.
- Manny returning Roshan to his father, and reconciling with him.
- Just the look on the father's face when he sees Roshan; he practically lights up.
- The goodbyes between them and Roshan.Sid: Don't forget about us, okay?
Manny: We won't forget about you. - After all he has endured, Manny now has a reason to live again. He is thanking Roshan for giving him the strength to move on with his life, and for giving him a family again.
- Even Diego shows up alive and well, and cheerfully plays "Where's the baby?" one last time to Roshan, before the humans leave entirely.
- The ending of the film is very sweet. After their journey together, the three main character are close friends and head south together. They wouldn't dream of abandoning each other now. Seeing them just chat about their trip is touching as it establishes their close friendship.
