Born at 37 weeks weighing a combined total of 10 pounds, the boys -- who weren't expected to live -- share more than a special bond; they share a liver and a malformed heart.
Their birth and subsequent medical care touched off debate among doctors and medical ethics experts who said the conjoined twins are destined to die.
"Kaydon, he's very laid back. He'll sleep all day if you let him. Kameron is very curious, social as well. He has a temper -- knows what he likes and what he doesn't like," Manns told WGN-TV in Chicago, before the twins celebrated their first birthday Thursday.
"Even though they are conjoined, they are two separate babies to me," Manns told the Chicago Tribune for a story published today. "They are very different in every type of way."
Medical experts said the twins can't be separated and aren't candidates for a heart transplant because of their complicated anatomy.
Last summer, doctors at the University of Illinois Medical Center at Chicago -- where the twins still are hospitalized -- described the emotional toll of caring for them. They worry that their interventions went too far, expressing concern that the infants are the ones who would suffer.
"As health care providers, knowing what we know, we don't want to see the babies die in an agonizing way," neonatologist Dr. Helen Kusi told the Tribune at the time. "That's where we are not on the same page with [the mother]. We haven't given up, but we have to face reality."
At the time, the twins were unable to breathe without a ventilator and were fed through tubes. The babies periodically went into distress and had to be resuscitated to prevent them from dying.
Today, doctors told the newspaper, Kameron breathes without assistance and Kaydon, who is doing most of the breathing for the two, is being weaned off the ventilator. They no longer experience the medical crises that require resuscitation.
But as they celebrated their birthday, Lisa Anderson-Shaw, director of the medical center's clinical ethics consult service, said that just because the twins reached this milestone doesn't make the aggressive treatment the right decision -- or the wrong one.
"We had the option early on to not do heroic measures and to allow the mom to have time with the babies and then allow a natural death," Anderson-Shaw told the Tribune. "Now that option is not the same. ... It brings up more complicated choices down the road."
Dr. Susan Kecskes, a UIC pediatric intensivist, told the newspaper, "Right now we know that, at some point, they will outgrow their ability of their heart to support their body, and then they'll get sick again and there won't be anything, ultimately, that we'll be able to do for them."
But for now, Manns spends several hours every day with her boys. She travels up to two hours daily, taking public to and from the hospital after work. She plays with them, washes their hair and joins them in their hospital bed, holding them close to her heart.
She organized their birthday party Thursday, turning it into a festive celebration with balloons and two cakes. The guests of honor wore blue crowns, each decorated with a gold number one. Relatives sang "Happy Birthday" as they gathered around the boys' hospital bed.
Fighting back tears, Manns struggled to talk with a WGN News reporter about how she prepares for the day her sons no longer are here.
"At the end of the day, they know I loved them," she said. "And I know they loved me."