National Geographic & ITV

As quirky and extraordinary as its native land, the red kangaroo – king of the Outback – now shares its home with some new and deadly invaders – commercial trucks. Cheryl Grills and Sheila Firth are dedicated to raising the orphaned joeys that the trucks leave in their wake. And that’s no small task; kangaroos are efficient breeding machines. At any time, a female might have an embryo in her womb, a “pinkie” in her pouch, and a joey hopping around beside her.

Hoping to prevent orphaned joeys from becoming secondary casualties of the fast-moving iron-and-steel predators, Cheryl and Sheila welcome young kangaroos like Sweet Pea into their families, giving them all the TLC a little roo could need. It’s a round-the-clock job for the surrogate moms, who consult scientific advisors to help them develop the appropriate regimen for their foster families.

As the day approaches for the rehabilitated Sweet Pea to be released back into the wild, Cheryl and Sheila have mixed emotions. Sad to say goodbye to a cherished animal but happy to see Sweet Pea return to the wild.