Claude (left), Carlotta (middle) and their hatchling Cathy.
PERFORMER Jerry Nelson (Claude)
  Stephanie D'Abruzzo (Carlotta)
  Alice Dinnean (Cathy)
DEBUT 1997

The Cuckoos (emphasis on the "oo") are a family of cuckoo birds who moved into Big Bird's nest in Sesame Street Episode 3564.

While Big Bird is at Hooper's Store having a birdseed milkshake, Claude and Carlotta Cuckoo spot his nest and move in so they can hatch their egg. As is cuckoo custom, the cuckoos don't have nests of their own and borrow empty nests from other birds in the event of an egg hatching. Big Bird agrees to let them stay until the egg is hatched, but is soon roped into "babysitting," which entails sitting on the egg and singing "The Alphabet Song." Another cuckoo custom is getting someone else to sit on their egg.

The egg eventually hatches, and Big Bird names their baby "Cathy." However, Claude and Carlotta decide to stay longer, not wanting to remove the child from the only home she's ever known. Ultimately, Big Bird convinces them to move to another empty nest in the park.