At the Denver Zoo, a male orangutan has taken on a role unusual for his species: Mr. Mom. After Nias, a 32-year-old female Sumatran orangutan, died from an unexpected heart attack on December 17, she left behind two daughters: Hesty, 10, and Cerah, 2. By Tuesday, Jan 12, Cerah's father, Berani, had "stepped up to the plate" to take care of the 2-year-old orangutan. "In the wild, orangutan males are not involved with their offspring. To see Berani step up as Mr. Mom, is an extremely rare situation -- and Cerah couldn’t have asked for a better dad," zoo officials said. "Berani is so attentive and protective of her, seeing to all her needs. He will carry her, comfort her and even snuggles her when she sleeps." Officials note that Cerah's 10-year-old big sister, Hesty, also helps care for Cerah and plays with her during the day. "The three of them are sticking together and moving forward."