A professional mixed martial arts fighter has donated the organs of his 15-month-old son who was mowed down by an alleged drunk driver over the weekend while he was sitting inside his stroller.

Marcus Kowal and his wife took their baby, Liam Mikael Kowal, off life support on Sunday after doctors declared the infant brain dead. “He tried to fight so hard. He even died at one point but they brought him back. He’s a little fighter,” the Sweden-born athlete wrote on Facebook.

“Our hearts are broken and there’s a void in my soul but we will get through this,” he added.

The couple decided to donate their son’s heart so it “can make another child live” and prevent another family from going through the same heartbreak, Kowal added. “It hurts to write this but Liam loved to share and the person we were going to raise him to be would love to help someone else,” Kowal said, urging his Facebook followers to message him if they knew of any child in need of a new heart.

Their young son’s life was cut short Saturday after a 72-year-old woman plowed her SUV into the baby and his 15-year-old aunt while the two were crossing the street in California, police said in a statement. A police photo of the accident scene shows the stroller broken in half.

The driver, identified as Donna Marie Higgins, was allegedly intoxicated when she drove through a crosswalk, struck both victims and then attempted to flee, according to the Hawthorne Police Department. Witnesses chased after Higgins’ vehicle for about a block and blocked her SUV with their own cars until police arrived. Authorities said Higgins was arrested for felony hit-and-run and felony drunk driving.

Kowal’s wife, Mishel Eder, mourned her son in an emotional Facebook post and remembered how the happy boy loved to eat, swim, count in Russian, chase dogs and help wash dishes. She wrote about his smile and how she felt putting her son in bed after he had fallen asleep in his father’s arms.

“I’m shattered. So is Marcus. Our little family is broken,” Eder said. “Last time we were in the hospital, he was born. Now the light of my life is being taken away.”

The family’s heartbreak has touched hundreds of people across the world. More than 1,000 people have donated over $81,000 to an online fundraising page set up to help the family pay for medical expenses and funeral costs.

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