Vivian is new to the zoo, and had to be quarantined from her mate, Taji, for 30 days.
The two were ready to be together after that, but there was a problem, Vivian wouldn't take her birth control.
The two aren't good genetic matches so the zoo doesn't want them to breed.
This week, Vivian finally decided to cooperate.
The zoo is giving her the contraception in a lettuce roll, and now the two gentle giants are a match made in zoo heaven.
"That's why we take so much time and care when we introduce animals to the new exhibits and to each other. You really don't know if they're going to be compatible," says Dawn Petefish with the Peoria Zoo.
All zoos in North America coordinate to maintain genetic diversity between animals.