The fire happened earlier in December while the family was asleep in their home that sat just above the Brookdale post office in the Santa Cruz Mountains. Some of them made it out quickly but Rosston was still inside.
"I was terrified," the 11-year-old said. "I didn't know what to do."
Nelson and her fiancé were frantic outside - he busted a window on the second floor trying to get everyone out, injuring himself in the process. Each second Rosston was still inside, grew more agonizing.
"Any mom's worst fear is something like that happening," Nelson said in tears. "I never ever experienced that. I don't ever, ever wish that for anybody, especially if you have kids."
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Nelson says it was a Ben Lomond firefighter who eventually saved Rosston's life.
"Nick Burgess is the firefighter that pulled him out," she said. "I just wanted to tell him thank you so much."
That gratitude, extended to all local firefighters, including Santa Clara County Fire Department who delivered toys on Christmas week to Rosston and other young patients at Santa Clara Valley Medical Center who couldn't be home for the holidays.
"The support that we got from the community and from everyone and now the firefighters, it's just overwhelming. So amazing," said Sophie Lang, a mom whose young daughter was at Valley Medical after suffering a stroke. "We're just so grateful for everything."
The firefighters are just as thrilled by the special day.
"It's very heartwarming. It's definitely a little emotional, but, we're just very excited that we can do this for these children," said Matt Mokhtarian with the Santa Clara County Fire Department.
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Rosston is still recovering from burns and smoke inhalation.
His family is without a home and will be staying in a local hotel.
Still, they're grateful that the rest of their loved ones who escaped the fire are out of the hospital and Rosston was eager to join them.
"I really feel like there was somebody watching over him that night," Nelson said.
A GoFundMe was set up for the family. To find out more, click here.