A mixed martial arts fighter posted a heartbreaking farewell to his 15-month-old son, who died days after he was struck in his stroller by a suspected drunk driver in California.

Liam Mikael Kowal was pronounced brain dead after the Sept. 3 incident and the family chose to remove him from life support yesterday.

"Good night bebisen (baby), you'll always be with us. Pappa älskar dig (Papa loves you)," Kowal wrote, posting a photo him holding his son's scratched hand.

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Kowal also posted a sobering video on Instagram just hours after his son's death, imploring people not to drive drunk.

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"I’m not a paid actor. This is not a commercial. This is reality," he said.

"All I can say is don’t drink and drive. Don’t let a friend drink and drive. Please."

Kowal, a native of Sweden and former professional kickboxing champion, competed on the MMA circuit and now focuses on training and coaching fighters.

A GoFundMe page has been set up to raise money for the family and more than $100,000 has been given. Kowal's partner and Liam's mother, Mishel Eder, wrote on the page:

"Saying good bye to my light, my love before he goes to save lives. This pain is unbearable. Liam, I love you. Hug your children, kiss them always. Don't lose patience. Laugh with them often. Get off your phones and play games. #rememberliam."

Eder's teenage sister was walking with Liam when they were struck by the SUV and she is in stable condition, according to the GoFundMe page.

The driver, 72-year-old Donna Marie Higgins, drove off after striking the children at a crosswalk in Hawthorne on Saturday afternoon. Police quickly caught up to her, with help from witnesses, and took her into custody. 

Higgins was arrested for felony hit-and-run and suspicion of drunk driving and was reportedly being held on $100,000 bail. 

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