The first teaser shows that unlike in the original movie, there are humans in this version who show the titular elephant genuine kindness. Most notable among these humans is Milly, who coaxes the little guy out from under the hay pile he's hiding in with some reassuring words.
Milly: We're all family here, no matter how small.
Doubling also as a Tearjerker, but it's also sweet watching Joe and Milly give Dumbo a comforting hug. It really shows that these two will play a key role in helping the little elephant rise to stardom with their friendship.
Near the end of the teaser, Milly is seen giving Dumbo the "magic feather", telling him to "show [the audience]" what he can do.
Milly's reassuring little Dumbo and telling him that they're all family is really sweet, especially since very few humans in the original seemed to care about him. Milly, however, tells the little guy that he's not alone, and that there are people in the world who are willing to care for outcasts like himself.
When the circus troupe hears that Vandemere plans to kill Dumbo's mother, they make a plan to get Dumbo free.
It's shown in the epilogue that Max Medici changed his circus's name from Medici Bros to Medici Family, suggesting he sees his troupe as his family.