My baby and husband were killed by a drunk driver. Here's my plea before you get behind the wheel.

"On that day, everything had changed."

It was a typical Saturday evening on Sept. 20, 2014, for Missouri mom Destiny Klimaszewski.

She and her husband Corey Mantia were driving to meet a friend. Their 1-year-old son Parker was strapped in his car seat behind them.

"I then took what would be my final pictures of my sweet baby."

Klimaszewski married Corey on July 30, 2011. The two were high school sweethearts who had met as teens at a football game.

"I was the light of his eye -- he absolutely adored everything about me," Klimaszewski said of Corey. "He always put me first and he taught me what love was."

"His whole world revolved around Parker," she said. "It didn't matter how long of a day he worked, he still wanted to come home and play with him."

Klimaszewski and Corey welcomed their little boy on June 23, 2013. Klimaszewski described Parker as a happy baby who loved Mickey Mouse, swimming and painting pictures.

"He was definitely a mama and daddy's boy--he didn't want anybody but us," she recalled. "He just seemed so advanced. He hit milestones way sooner than most babies his age."

"I almost felt like it was the universe allowing me to experience all the things I wasn't going to get to experience."

"On that day, everything had changed."

On the night of their drive, a motorist hit the driver's side of Klimaszewski and Corey's silver minivan.

The Missouri State Highway Patrol noted in its traffic crash records that the Sept. 20 accident connected to Klimaszewski's family involved alcohol as a contributing factor in the crash, on the part of the other driver.

Baby Parker died at the scene, whereas Corey, after fighting for his life for almost 24 hours, died less than a day later.

Klimaszewski was the sole survivor of the crash in which the woman who hit them also died.

Klimaszewski was hospitalized for non life-threatening injuries.

Klimaszewski said she's fortunate in that she does not remember the accident.

"The trauma basically wiped all those memories away," she added. "I do know that my mom had to have me heavily medicated -- I kept asking where my baby was. I couldn't grasp the concept that he was gone."

"Everything I lived for was gone."

Klimaszewski was discharged two weeks after the incident. She left the home she shared with Corey and Parker, and moved in with her parents.

"I was so lost and scared. I didn't know what to do because everything I lived for was gone," she said. "I didn't have my little wake-up call or my husband asking me, 'What's for supper?'"

"I felt like I didn't have a reason to get up, or breathe anymore."

Klimaszewski looked for support from her family and friends.

One month after the crash, she met her now husband, Brett Klimaszewski. The two were introduced at a get-together held at Klimaszewski's brother's house.

The couple started off as friends, and later married on May 20, 2017.

"I say all the time that my husband who passed away had a hand in this and sent him to me," Klimaszewski said. "Brett saved my life. He was just my rock. He was my safe place. There were times when I went back and forth about being in a relationship, but he just never went away."

On Feb. 6, 2018, the Klimaszewskis welcomed a son, Cohen, now 2.

Like Parker was, Cohen is happiest when he's with his parents, Klimaszewski said.

"I was really scared to enter parenthood again," she said. "I was worried that emotions would come back and I wouldn't be the mom I was able to be."

"He's a spitting image of Brett, where Parker was a spitting image of me. Cohen is very independent and he's a mama's boy."

"What I miss most..."

Klimaszewski was just 21 years old when she lost the two most important people in her life.

She said she misses her innocence, and sometimes fears she's losing memories of Corey and Parker.

"It's five years in and I'm starting to forget the little things that meant the most -- their laugh, their smell. It almost seems like it's a world away now. I still can't watch videos and hear their voices because it's too strong of a trigger."

Klimaszewski once felt a lot of anger toward the driver who was at fault in the crash, but has learned compassion.

"I have to think about her family and they have to live without someone they love, too," she said, "If I sit and stay mad ... I'm letting her take something else from me. What really helps is knowing that this life on earth is temporary and later, with my faith, I get to spend eternity with them."

"It's important to me to keep their memory alive and fulfill the dreams we once had."

Making a difference, in Corey and Parker's names

Since Corey and Parker's deaths, Klimaszewski has honored them by performing random acts of kindness, and holding toy and backpack drives for children in need.

Three years ago, a street sign for Corey and Parker was revealed on the stretch of road where the accident occurred -- reminding others to never drink and drive.

Klimaszewski also launched a local Modern Widows Club chapter.

"I want to show people it's possible to have joy without forgetting," Klimaszewski said.

According to data released by the National Highway Traffic Safety Administration (NHTSA), drunk driving claimed the lives of 10,511 people in 2018 alone.

With December being National Drunk and Drugged Driving Prevention Month, Klimaszewski agreed to share her story and raise awareness at a time when getting behind the wheel under the influence may be more prevalent during the holiday season.

Helen Witty, national president of Mothers Against Drunk Driving (MADD), became involved in the organization 19 years ago when her daughter, Helen Marie, was killed by a teenager who was driving while drunk and high on marijuana.

Helen Marie was 16 years old when she died. She had been rollerblading when she was hit by the motorist.

"When she didn't come home, my husband went looking for her," Witty told "Good Morning America." "He had to identify her at the scene. That shattered our lives and changed everything. [MADD] gave me hope because I really wanted to die. The bad news [was], 'I'm going to live,' and I didn't want to live with this pain."

"They showed me I could live," she added. "I could heal and I could help others."

Witty now dedicates her life to honoring Helen Marie by speaking to the public about the consequences of driving under the influence of alcohol.

Here are tips, takeaways and reminders according to Witty and Klimaszewski, before you get behind the wheel:

1) Having drinks? Then have a plan.

Since losing Corey and Parker, Klimaszewski has advocated against impaired driving.

Today, she and her husband Brett discuss who is going to drive before they have drinks. Whoever is drinking doesn't drive, she said, even if it's "only" one drink.

"It's simple," Witty says. "If you drink, don't drive. If you drive, don't drink."

2) Take advantage of ride-sharing apps and remember, the alternative is worse.

Between Uber, Lyft, cabs and more, there's plenty of affordable resources.

Witty offers this reminder: Weigh the cost of a cab or ride-share compared to at least $10,000 in fines, jail or prison time -- plus risking your life, and the lives of others.

"Nobody gets in a car and turns it on by accident," Witty said. "The difference between a DUI and a DUI fatality is chance. It's one second."

"The family of the person you killed will not consider it an accident," she added.

3) Even if you don't drink and drive, you could stop somebody else from doing it.

Klimaszewski suggests being a voice of reason to friends and family who might drive impaired.

Take away their keys or "pay for the cab, offer to drive them home," she says. "If you can't be that voice of reason, take down their license plate number and call it in."

Witty says, "Understand, alcohol impairs you, even from the first drink."

"It's senseless death and it's heartbreaking, as Destiny will tell you," Witty added.

Read more on the consequences of drunk driving and how alcohol affects your driving ability on the NHTSA's website.

MADD also has a 24/7 victim helpline. If you've been impacted by a drunk driving crash, dial 1-877-MADD-HELP or visit MADD's website.

If you're struggling with addiction, the Substance Abuse and Mental Health Services Administration can help you locate a treatment facility. Their helpline is free, confidential and open 24 hours a day: 1-800-662-HELP (4357).

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