Mom who suddenly lost her 4-year-old son to the flu: Please get vaccinated early

Ashley May | USA TODAY

Show Caption Hide Caption The truth about the flu shot With weather changes comes the inevitable start to flu season, if you are still debating whether to get your flu shot or not this year, here are some truths you should know about getting vaccinated. Susana Victoria Perez has more.

A mom and physician was left shocked and heartbroken after her healthy 4-year-old son died within two days of showing flu symptoms.

Leon Sidari died on Christmas morning last year.

He was scheduled to receive his flu shot during a routine checkup days later, mom Laura Sidari said. The boy was known for his infectious smile and gentleness.

"The flu shot fell through the cracks for my children in the midst of caring for my large family at a very busy time of the year," she told USA TODAY. "I have compassion that this also happens for many other excellent and smart parents."

The symptoms she noticed in her son before that day were all but common: fever and body aches. But, hours later, her son who rarely got sick had trouble breathing, and Sidari said she rushed him to the emergency room. He had bacterial pneumonia and the flu, doctors told her.

“In the hospital, there came a moment when my brain knew that my son was dying, but my heart simply did not,” she told People. “In medical training, I can remember similar moments in the critical care setting, where death approached like a train hurtling towards its final destination. However, as a mother, nothing can prepare you for watching your child die.”

More: Unvaccinated child dies from the flu in Florida, state health officials say

Now, Sidari, who lives in Ohio, is pleading with other families to be proactive about getting flu shots as soon as possible. She recently shared a photo of her husband, also a military physician, and their younger sons Tristan, 2, and Cameron, 11 months, after receiving their vaccines this year.

"Leon is my reason this season, and every season, for getting flu shots on time," Sidari said.

She's encouraging others to share their flu shot photos using the hashtag #FluShotsForLeon.

Follow Ashley May on Twitter: @AshleyMayTweets