ST. JOHNS COUNTY, Fla. -

A grieving family is speaking out, asking drivers of all ages to be careful out on the road.

It comes after Thursday morning's fatal crash in St. Johns County that claimed the lives of 20-year-old Alyssa Nearbin and 24-year-old Joey Stevens and critically injured 21-year-old Dylan Charles and 18-year-old Erin Aderhold.

Hosston Bishop, 21, suffered minor injuries.

Alyssa Nearbin and Joey Stevens The Florida Highway Patrol hasn't yet confirmed who was driving the SUV when it ran off the road and hit some trees on County Road 208 at County Road 13A South. Troopers said it could be a while before they know for sure. They do believe alcohol was a factor in the crash.

Stevens' family says no matter who was driving in this accident, all drivers need to remember to be careful.

"I keep waiting for him to walk in the door," said Jinny Stevens, Joey's mother.

A day after hearing the news of her son's death, the grieving mother placed a statue of three angels at the site of the accident. She said they're there to watch over other drivers at the intersection.

For Stevens' family, the thought of losing the 24-year-old is still hard to believe.

"I just hope he's in a better place and I'm glad he didn't have to suffer, and I miss him," Jinny Stevens said.

"He told her and we just couldn't believe. But now it's in the paper. I know for sure he's gone," said Wanda Billsborough, Joey's grandmother. "When it's in the paper, I know he's gone. I loved the kid so much."

Erin Aderhold and Dylan Charles Joey's mother said he was riding in the backseat of the SUV and was ejected by the force of the impact.

Aderhold and Charles (pictured, left) remain in critical condition at Shands Jacksonville Medical Center.

As for who was driving, Channel 4 crime and safety analyst Ken Jefferson said investigators can have trouble determining right away who was driving when multiple people are in the car.

"It's not unusual not to know right off the bat," Jefferson said. "But once they conduct their investigation and they do the things they do -- and it's pretty impressive stuff what they do -- they can make a determination as to who the driver was."

For now, the crash is still under investigation. For Jinny Stevens, the fact of who was driving isn't as important. What matters is that others will learn from what's happened. She hopes they'll listen.

"When you get behind that wheel, you're responsible for everybody in that vehicle," she said.

Troopers said the car has been processed and all physical evidence has been sent to the crime lab. They said it could take several months before the results return.