The toddler son of MMA star Marcus Kowal died after a car plowed into his stroller in Hawthorne, California, on Saturday, September 4. 

Liam Mikeal Kowal, 15 months, and his 15-year-old aunt were struck in a crosswalk at 4:15 p.m., Mercury News reported. The driver, Donna Marie Higgins, fled the scene, but witnesses followed her SUV and surrounded it until authorities arrived, according to the paper. 

Per a press release issued by the Hawthorne Police Department, Liam’s teenage aunt suffered “from what appeared to be leg injuries,” while he was found “pulseless and not breathing.” 

Higgins, 72, was arrested on suspicion of hit-and-run and drunken driving and booked into Hawthorne jail with a $100,000 bail.

“I saw [Liam’s] stroller in two pieces,” Kowal told ABC7. “And he had a  little green frog that he’s had with him since day one … and he carries around wherever he is. He won’t sleep without his green frog, and it was lying in the middle of the street.” 

Teaching him Michael Phelps stuff. #swimming #baby

A video posted by Marcus Kowal (@mackowal) on

That evening, Kowal and his partner, Mishel Eder, took to his Facebook page with a sad update from Harbor-UCLA Medical Center.

“About an hour ago, our baby was declared 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 professional kickboxer and mixed martial arts athlete wrote. “His heart is still beating, but his brain is no longer working. Our hearts are broken and there’s a void in my soul, but we will get through this.”

Liam was disconnected from life support later that night.

“I’m a fighter, I can take pain, I’ve taken pain my whole life and nothing hurts as much as this,” Kowal told ABC7. “I was proud to be a dad and I wanted to raise a good child.” 

Kowal and Eder are donating Liam’s organs. “So his heart can live through another child,” Kowal explained to the station. “He loved to share, so I know he would have wanted to share his heart.”

A GoFundMe account was set up to help the family with medical expenses and funeral costs.

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