Milan Rossignol's parents say he was born to rock, and from the very first time the three-year-old from Lavaltrie heard his dad playing Metallica, Milan was hooked.

“When their music comes on, he does things with his hands, his feet, they're always moving. They continue to the beat all the time,” said his mom, Catherine Perreault.

Sadly, these days Milan has to do most of his rocking out at the Montreal Children’s hospital while battling a rare disease called Langerhans Cell Histiocytosis, which has severaly affected his lungs and liver.

Milan is currently undergoing chemotherapy, but his medical team says somehow milan manages to stay positive.

“He's so charming, he doesn't speak but he has a way of communicating his desires, things he's happy about, things he's not happy about,” said pediatric oncologist Sharon Abish

His doctors' were so taken with Milan's spirit, they decided to reach out to his favourite band. Metallica drummer Lars Ulrich had a zoom meeting with his number one fan.

Metallica didn’t want the conversation recorded, but Milan’s father says he was extremely moved by the whole story.

“He told us how happy he was that his music gives Milan such joy,” said Yannick Rossignol. “He told us he would send Milan a shirt and he wants a shirt with Milan on it. He was very nice and very cool.”

The meeting was a huge morale boost for Milan’s parents, both of whom had to quit their jobs to be with Milan as he receives care.

Aside from the emotional toll, they had to start a Gofundme page to pay their bills and, hopefully, fund research into the disease.

But what keeps them going is seeing Milan happy, and his parents say nothing puts a smile on his face as much as playing on his toy drums and headbanging to Metallica.

“This Metallica thing, I have to say I don't get it,” said Abish. “But he gets so excited every time Metallica comes on the screen and dad and him just rock'n roll and they have a great time.”

“My boy is very awesome,” said Perreault. “He's Super-Milan. When I'm crying, he just puts his fingers (on my tears) and wipes them away as if to say 'No, no, we continue the fight.'”

Milan’s dad says his dream is that his little boy will one day be healthy enough to see his favourite band live.