When Jill Noe's sister, Whitney Bliesner, couldn't get pregnant, Jill volunteered to serve as her surrogate for twins.
Bliesner was diagnosed with a rare genetic disease called Neurofibromatosis type two or NF2.
According to the U.S. National Library of Medicine, NF2 is the growth of noncancerous tumors in the nervous system.
Noe is now 30 weeks along in the pregnancy with a healthy set of twins, a boy and a girl. They are due on June 6.