When your child is sick and you don't know what's wrong with them, parents usually turn to doctors. But what does a parent do when the doctors can't diagnose what's wrong with your child?

Natasha Durling found herself in this situation when her son, Oliver, became sick and started experiencing symptoms like vomiting, diarrhea and sore muscles.

She called her doctors, who weren't sure what was causing the symptoms. They dismissed it as a virus that would likely pass within a few days, but to take him in if his fever got too high or lasted more than five days.

Over the next few days, poor Oliver's illness grew worse

Oliver was no longer eating or drinking.

The worried mother kept worried friends and family updated with Facebook, posting how Oliver had never been this sick before. She wrote, "Monday morning comes along, he's even worse. He's not eating or drinking at all, won't get up, not using the bathroom and now has a slight rash forming on his neck and face. He has swollen lymph nodes and his eyes are completely bloodshot. I panic ... and [get] myself"‹ ready and head straight for Annapolis hospital to have him checked out."

When they arrived at the hospital, emergency nurses immediately quarantined Oliver out of fear that he might have measles.

The doctor examined Oliver and confirmed that it wasn't measles, and suggested Tylenol and Benadryl, again dismissing it as a virus. The doctor sent the family home, even though Oliver was clearly in pain and severely dehydrated.

Oliver woke up the next morning complaining that his leg hurt and he was afraid he might be dying.

"He is covered from head to toe in the worst rash I have ever seen," Durling said. "His fever (with Tylenol and Benadryl) was past 40° (104 Fahrenheit) and his lips were so swollen that they were cracked and bleeding."

At this point, Durling had had enough. She was tired of watching her poor boy suffer in agony and not be able to do anything about it.

She again took him to the hospital, where he had some blood work done and given an IV.

But things only got worse

While Oliver was trying to get a urine sample (and struggling due to his dehydration,) he started screaming, telling his mom he couldn't see and was going blind. His mother rushed to his aid, and he went stiff and fell into her arms, according to her Facebook post.

The nurse rushed him to the ICU, where the doctors were finally able to find a diagnosis - not measles, but Kawasaki disease, a heart disease that causes inflammation of the heart and blood vessels.

While Kawasaki is rare, it is fortunately treatable. It is most commonly found in infants and toddlers, but once diagnosed, they recover within a few days.

After his diagnosis, Durlingsaid her son went through blood transfusions and "screamed in pain all night from his inflamed blood, stomach pain and inflamed joints and he throws up several times."

Luckily, the next morning he was feeling better. His rash wash gone and his fever was steadily dropping.

The battle wasn't over yet

The nurses said Oliver was well enough that he could go home, but Durling insisted on staying a couple more days. She wanted to ensure her son would be all right.

That evening, Durling was taking her son for a walk around the hospital wing to avoid cabin fever. The nurses found her and urgently ushered the two of them back to Oliver's room. They told her that her son's urine tests had, in fact, tested positive for measles.

Oliver was quarantined and everyone around him made sure to take safety precautions - including masks and protective gowns.

"Ollie is the ONLY known case of contracting measles while having all his up to date immunizations"‹, and Kawasaki disease at the same time," Durling said. "I have one strong, brave little man! I couldn't be more proud of him!"

Oliver was treated for measles and was discharged from the hospital for a second time, but once again, his mother refused. She insisted that they stay until all of his tests came back normal.

Durling urges parents to trust their guts. "Fight for your kids if something doesn't seem right! We know our kids, so don't take no for an answer" she wrote on her Facebook update. Durling is a great example of a persistent mother who knows what's best for her children. Trust your instinct as a parent and do what you believe is best for them.

The family has started a GoFundMe account to help pay for Oliver's medical expenses, which can be accessed here.