The Stepford Cuckoos are a set of fictional mutants, psychically linked quintuplets appearing in American comic books published by Marvel Comics. The alphabetical order of the Cuckoos’ first names corresponds with their ages, with Celeste being the firstborn and Sophie being the youngest. Originally calling themselves the Five-in-One, with the deaths of Esme and Sophie the remaining sisters are now known as the Three-in-One. They are students at the Xavier Institute for Higher Learning.