In the final days of 2019, Abigail and Micaela were born at UC Davis Children's Hospital. They were joined at the head, a condition called craniopagus twins. Conjoined twins are already extremely rare, but craniopagus twins are even more so. Only two percent of conjoined twins are born fused at the head. After a safe and successful delivery, UC Davis doctors and nurses began planning for a possible separation surgery.