Marcus Kowal has endured a range of emotions since he saw his son’s stroller split in two, lying in a Southern California street.

There was the initial anguish — so bad that Kowal, a professional mixed martial arts fighter and instructor, had to be calmed by officers who responded to the scene after a suspected drunk driver struck the stroller.

There was hope when first responders said Kowal’s 15-month-old child, Liam, was breathing on his own, then a disorienting mix of sadness and optimism when doctors later said Liam had brain damage.

Donna Marie Higgins (Hawthorne Police Department) Donna Marie Higgins. (Hawthorne Police Department)

A day after the crash, Kowal’s son died, triggering overwhelming grief.

But Kowal says one emotion has been missing since Saturday, when Liam was struck: hatred.

“I’m really surprised actually that I don’t feel any rage,” Kowal told CBS News. “I haven’t felt any rage; I don’t feel any hatred.”

Police suspect Donna Marie Higgins had mixed alcohol and prescription medication before getting behind the wheel of her SUV on Saturday in Hawthorne, a city just minutes from Los Angeles International Airport.

Her SUV struck Liam and his 15-year-old aunt, who was walking with the toddler on the way to lunch.

The teenager, who has not been identified by authorities, was taken to the hospital with leg injuries but is expected to recover.

Higgins tried to run away after the crash, according to police, but she was stopped by passersby near the restaurant Liam and his young aunt never reached.

Higgins was initially charged with felony hit and run and felony drunk driving, but her charges were upgraded Wednesday to felony vehicular manslaughter. The 72-year-old was released on $100,000 bond.

Kowal, a Swedish national who now lives in Southern California, arrived on foot at the horrifying scene shortly after the collision.

His son was transported to Harbor-UCLA Medical Center, where he was admitted to the ICU.

After Kowal and his wife learned their son was brain dead, they decided to take him off of life support and donate his organs.

Kowal asked friends and followers on Facebook to message him if they knew of someone with a child in dire need.

“This isn’t easy to write but Liam is going to donate his organs, so that his little heart can make another child live and another set of parents not have to go through what we have to,” he wrote on Monday. “We were told that we can donate to someone we know. Therefore, I am writing this post to ask if there is a child out there we know that needs a heart or any other organ.

“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. So anyone we know, or someone you know, inbox me please.”

Good night baby, you will always be with us. Pappa älskar dig. #RIPLiam

A post shared by Marcus Kowal (@mackowal) on

A GoFundMe campaign to cover medical expenses and funeral costs had raised more than $125,000 as of Thursday afternoon. Kowal, who owns a series of MMA training centers in Southern California, said his family may use some of the money to start a nonprofit in Liam’s memory.

“As heartbreaking and devastating as this has been, nothing comes out of it if we don’t turn this into something positive,” he said.

Many of the donors to the campaign were strangers.

Among them: Will Ingraham, who gave $20 and wrote, “Our son’s name is Liam and we are grieving your loss with you. We are so sorry to hear of this pain and selfishness that this world caused. From strangers from afar, we love you.”

At a news conference Wednesday, outside one of his training facilities, just blocks from the spot where his son was fatally injured, Kowal said he was feeling a new emotion: hope.

His son’s organs have been donated to multiple people, he said, including an infant, who received the boy’s heart — new beginnings out of Liam’s tragic end.

“There is a God, no matter what his name is,” Kowal said. “I am so sure that he will be happy to see a set of happy parents and a living child rather than see what we’re going through right now. That’s the reason we chose to donate Liam’s organs — so  another set of parents don’t have to go through what we’re going through.”

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