It might have looked like heat rash, but something told Danielle McNair to keep asking questions.

As Fox News reports, the Georgia mom was concerned about her son from the moment she noticed that he had a tick bite. As Danielle wrote on Facebook, several weeks ago, her 5-year-old son, Mason, got a tick in his belly button. Though they managed to remove it, the area soon became inflamed. So the worried mom took her son to the doctor.

Noting the infected bite and the fact that Mason was simultaneously suffering from impetigo, the doctor gave the boy an antibiotic. However, instead of getting better, Mason got worse. Danielle wrote:

Mason started to get other symptoms including fatigue, diarrhea, fever, headache, and pain in his abdomen. On the last day of his meds he suddenly got a rash from head to toe.

About two weeks after the tick bite, Mason came down with a rapidly-spreading rash. Danielle wrote that, “At first the rash looked like it was just heat rash from being outside all weekend and how miserably hot it was. It started off small but within 8-10 hours it was already getting worse.”

The next morning, the rash was even more severe, and Danielle took her son back to the doctor. Medical staff told Danielle that Mason was probably reacting to the antibiotics. They were sent home again, but she wasn't happy with that diagnosis:

I was NOT satisfied with that answer and neither was my sister, who told me they needed to do a tick panel on him. I called back after doing my own research on tick-borne diseases and showed them what I had found on Rocky Mountain spotted fever.

According to the National Institutes of Health, Rocky Mountain spotted fever (RMSF) is caused by bacteria that can be spread to humans through a tick bite. Despite its name, RMSF is found throughout the U.S., and recent cases have been in Eastern states, from Virginia through Georgia, Tennessee, and Oklahoma.

Carried by the dog tick and wood tick, RMSF can even be transmitted by crushing a tick with one's bare hands. Symptoms of RMSF include chills, headache, pain, nausea, confusion, and diarrhea. Not all sufferers come down with the RMSF rash, which usually starts a few days after the infected tick bite.

Left untreated, RMSF can lead to pneumonia, brain damage, heart, kidney, or lung failure, meningitis, and death.

Confronted with Danielle's information about RMSF, Mason's doctors took another look at his symptoms and agreed with the mom's assessment. They started him on new antibiotics immediately, and he has since recovered completely.

After learning how serious RMSF can be, Danielle wrote that she is grateful she didn't take the doctor's initial diagnosis at face value:

This has been a horribly scary experience for our family. I’m thankful that I did my own research and brought it to my doctors attention. So don’t EVER be afraid to be an advocate for your child or yourself when it comes to things like this!

She says she has no ill-will toward her son's doctors for missing Mason's RMSF at first, noting that they “are humans and have to figure out the puzzle just like the rest of us do.”

Danielle is now sharing the experience to warn others to check for ticks and be aware that RMSF is present in their area of Georgia. She also wants other parents to understand the importance of following their instincts. She wrote:

“I am SO THANKFUL that I looked on my own and made sure I did not stop until I had the answer for what was happening to him!!!”