According to sister Elysha Hunter, there was a time when her younger brother, Nathaniel Omli, 9, thought he might be a robot.

One of the reasons was all the wires and tubes sticking out of him during one of his stays at Seattle Children’s Hospital.

Hunter laughs as she talks about her little brother’s confusion, which also in some way included their mom and Sponge Bob Squarepants.

Hunter also then starts to choke back some obvious tears.

A Bothell resident and barista at the city’s Caffe Ladro, with her employer’s help, Hunter has been trying to raise funds to aid her family in paying for young Nathaniel’s mounting medical bills, which now include a $500,000 heart transplant. And that’s just the latest major surgery for Nathaniel, whom Hunter said doctors refer to as a medical mystery.

According to his oldest sister, Nathaniel was born with two holes in his heart. Because of the extra work they had to perform, the new-born Nathaniel’s heart muscles were the size of those belonging to a 5-year-old.

“They all thought he was going to die when he was born,” Hunter said of her brother’s doctors.

Nathaniel apparently turned out to be a lot tougher than those doctors believed. But he still needed major medical procedures to survive. The first arrived in November 2007 when Nathaniel underwent a complicated surgery known as a Ross procedure which involved transplanting both the aortic and pulmonary valves of his young heart.

Hunter said the operation went well, but doctors noticed some kind of odd tissue growing on Nathaniel’s original aortic valve. While they didn’t seem to think it would be a long-term problem, doctors claimed it was something they had never seen previously.

“He’s just a unique case,” Hunter said.

Things went well for a while, but in February 2008, Nathaniel passed out during recess at school. Hunter said test after test came back negative and doctors were somewhat baffled. A heart catheter finally revealed the problem, namely a narrowing of one of the arteries leading to Nathaniel’s heart. Hunter noted doctors did not know what caused the problem, but heart stents were determined to be the solution. Hunter adds as far as can be determined, the type of stents needed never had previously been placed in an 8-year-old.

Eventually, Nathaniel had two more of the stents put in on the other side of his heart. Again, everything seemed fine. For a while. That odd tissue nobody thought was going to be a problem had been growing and was indeed becoming a major problem, one that eventually led to bypass surgery and finally a heart transplant in August 2008. An odd reaction to anti-rejection medicine led to a seizure and Nathaniel temporarily losing his memory.

At present, Hunter said Nathaniel is back in school and doing well. His sister said his heart medication has one side effect that some might find annoying, but her brother actually likes: big, bushy eyebrows and hair growing on his back. According to Hunter, Nathaniel doesn’t want those follicles trimmed.

“He’s got his sense of humor back,” Hunter said. “He plays baseball … He is the normal size of for his age for the first time in his life.”

Still, Nathaniel is going to need ongoing care and medications for the rest of his days. Hunter said medical insurance came nowhere near covering the cost of the heart transplant, just for starters. In a few months, the family will be responsible for up to 30 percent of Nathaniel’s future medical bills.

To help, Caffe Ladro’s around Puget Sound have been accepting donations and selling bracelets stating “One Heart.” The Bothell Ladro location (18610 Bothell Way N.E.) still is accepting funds and selling the bracelets. For those who can’t make it to Ladro and still want to help, they can donate by calling any Bank of America location and asking for the fund in Nathaniel’s name. In the meantime, Hunter and her mom are researching setting up some sort of charity for transplant patients such as Nathaniel.

“I am just so grateful for everything everybody has done,” Hunter said. “I just feel utterly blessed.”