Marcus Kowal
Screen grab of Marcus Kowal during an interview in 2014 YouTube/ Marcus Kowal

MMA star Marcus Kowal is mourning the death of his baby son after the 15-month-old was killed in a horrific hit-and-run accident. The fighter said he was still in tears after his only child with partner Mishel Eder succumbed to injuries sustained in the accident.

"About an hour ago, our baby was declared braindead. He tried to fight so hard. He even died at one point but they brought him back. He's a little fighter. His heart is still beating but his brain is no longer working," he wrote in an emotional Facebook post.

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"Our hearts are broken and there's a void in my soul but we will get through this.Again, your support means the world and I wish we could respond to each and every one of you but right now, we are going work through this.

"Funeral arrangements will be posted here. Thank you. RIP Liam Mikael Kowal. 5/25/2015-9/4/2016."

According to The Mirror, Liam was being pushed in his pram by Eder's 15-year-old sister when a suspected drunk-driver slammed into the pair. The accident occurred in California, and when emergency services arrived at the scene both were not breathing. While the teenager is in stable condition with serious injuries, Liam died in the intensive care unit of a Hawthorne, California hospital.

San Jose Mercury News reports that the alleged driver, Donna Marie Higgins, fled the scene but was arrested for felony hit and run as well as felony drunk driving after onlookers chased her down and cornered her nearby.

A GoFundMe page set up to help the family with medical expenses as well as funeral costs has so far raised more than $60,000. "As anyone can imagine, they are completely shocked, heartbroken, and have a long road ahead of them," a message on the site reads. "Please, if you can, donate anything you can to help them with medical expenses as well as funeral costs. I know Marcus and Mishel were giving their all to building a legacy business for their little family and they have impacted countless lives through their work. As Marcus's business associate and friend, I am starting this GoFundMe to organize our support. No parent should EVER have to bury their child!"

The support we have received from the Martial Arts world is unreal. From #BJJ to #KravMaga to MMA. Tears are running down my cheeks as I look at this picture of my little boy and read the message from @bashboxing and @cxf_mma #Repost @bashboxing with @repostapp ・・・ Our event #Sept10th will be dedicated entirely to the memory of Liam Kowal. If you have been to one of our fights chances are you know Marcus Kowal. To know the man, is to love the man. As the owner of @systemstrainingcenter and @systemstcencino Marcus is a huge part of our family. Fewer men posses a better attitude or general love of life than Mac. Today we received the worst news imaginable. His 15 month old son, Liam, was tragically killed when he was hit by a drunk driver yesterday afternoon. While in his stroller, Liam and his Aunt were in the crosswalk when an SUV barreled through them before fleeing the scene. Liam bravely, and valiantly fought for his life, but ended up succumbing to his injuries. At this time, all we can do is support Marcus, his wife Mishel and Liam's Aunt who was also injured in the accident. In order to do so, we will be donating a portion of every ticket sold to a fund in Liam's memory, that will be set aside for the family....We will also be holding a silent auction of some very high quality signed boxing and #MMA merchandise with the proceeds also being collected for the family. Please continue to pray for Marcus, Mishel and their family.....CXF4 Crossroads is now CXF "For Liam" #prayersforliamkowal #CXFForLiam #weareone @mrlightsout21 @bashboxing @lightsout_promotion @theclinchreport @custom_t_shirt_printing

A photo posted by Marcus Kowal (@mackowal) on