Finding out they were expecting twins was “scary news” for Mariah Carey and Nick Cannon.

“It was good news, but it was scary news at the same time because then that also meant that it was a high-risk pregnancy,” Cannon told Barbara Walters in an exclusive interview airing Friday on “20/20.”

 ”[The doctors] make you really aware that it’s very dangerous,” Carey said.

 Carey had already gone through a miscarriage, which contributed to their fears about a multiple pregnancy.

 The twins, named Moroccan and Monroe – Roc and Roe for short – were born on their parents’ wedding anniversary and are now six months old.  

 The couple “waited a long time to find out” the gender of the babies, Cannon said, and were excited to learn they were having one girl and one boy.

 ”I would carry around the ultrasound picture and be like, “You see that?!  That’s manhood,” Cannon said.

He told Walters that he would read to his pregnant wife’s belly, and they would play music to the babies as well through “a belly boom box.”

 ”You just put it on your belly and they hear [music] in the speakers from the beginning,” Carey explained.  ”Some of the songs are me.”

 ”You sang Stevie Wonder,” Cannon said.  “You sang your songs.”

 He added that his wife would cry when singing her song “Hero” to the babies.

Watch Barbara Walters’ exclusive interview with Mariah Carey and husband Nick Cannon, plus see their babies’ faces for the first time, on “20/20? Friday at 10 p.m. ET.