Tango is Elmo's puppy who made her debut in the 2021 animated Sesame Street special Furry Friends Forever: Elmo Gets a Puppy. The puppy then transitioned into puppet form in promotion for the special, and in Season 52. She is named Tango because she loves to dance.
In her debut special, it is shown that Elmo and Grover discover the stray animal in a cardboard box. On the way to a pet fair to find her a home, Elmo eventually decides to take her in instead.