For about 30 seconds, the Maryland defensive end couldn't hear people calling his name, urging him to get out of the van to greet his mom, Satta, for the first time since he was 8 years old.
"I literally froze. Everything went blank," Keihn said. "I just didn't believe I was finally sitting there."
When he finally emerged, Satta, standing on the porch, confused by the random vehicle's appearance, ran toward him, and the two hugged in tears. He told her he loved her, had missed her and was sorry it took so long to reunite.
So started Keihn's surprise return to Liberia, where he arrived June 30 with 14 years of longing to embrace his mom and left July 9 as a motivational figure to native children with a deeper determination to improve his family's conditions.
"It was an amazing feeling to have my mom in my arms again," Keihn said. "It was the most emotional feeling, but best feeling ever."
During their ensuing three-hour conversation on the porch, Keihn's worry that Satta wouldn't recognize him disappeared as they compared his passport from 8 and 22 years old, talked about her health struggles and reminisced about his childhood.
That night, when Keihn brought her from Kakata to his hotel in Monrovia, Liberia's capital city about 40 miles away, his mom sang and danced, thanking God for his safety and presence.
"She was just grateful," Keihn said. "It was the greatest feeling."
The next day, Keihn visited the Monrovia Football Academy, a comprehensive program started in 2015 to offer academic and soccer training for elementary school boys and girls.
The former Gilman star played with the kids for almost two hours and talked to them about his childhood experiences and life in America. He emphasized education as their most important asset.
He met with kids whose parents had died during the Ebola crisis a few years ago and spoke on a national radio broadcast about creating safe, playable sports fields and adding basketball hoops because the country hopes to promote the activity.
He later returned to the Monrovia Football Academy, taking a group picture, receiving a jersey as a gift and furthering his bond with 9-year-old Prince Toe, who wowed Keihn with his athletic talent playing on a team with 15-year-olds while succeeding in school.
"Love that kid," Keihn said. "He actually reminded me of myself."
For Gilman's Melvin Keihn, the NFL dream doesn't include the mansions and fast cars many young players envision. His dream is to use whatever he could earn with an NFL career to bring his mother to the United States and repay her sacrifice with a comfortable lifestyle.
Keihn hadn't forgotten about the cramped cities, but many of his memories were different.
He didn't remember kids having to do labor or the tendency for people to go to the bathroom in the streets. The big tree that used to hang over his mom's mud house was gone, and the ceiling and walls leaked during the current rainy season.
Such disparity from his life at Maryland left Keihn "more hungry to be successful than I ever have been."
"He was burdened with a heightened sense of responsibility," said former Gilman coach Biff Poggi, whose family housed and supported Keihn in high school. "This is going to impact the rest of his life."
With two more seasons of eligibility, Keihn plans to graduate next spring with a degree in family science, hoping to become a counselor for kids or people who've experienced traumatic events — unless he gets a chance in the NFL.
He wants to provide his mom safety and less grueling work in America.
"That is his No. 1 priority right now," his dad, Bainda, said. "He said he's going to work harder than ever to make sure that happens."
In the meantime, Keihn made Satta a promise.
After trying to teach her about his sport through a highlight video on his iPad — she was more concerned about players hurting Keihn than the sport's rules — and giving her a white Maryland football shirt with instructions to wear it every Saturday in the fall, Keihn told her he'd visit after his redshirt junior year.
He expects to start planning the trip five weeks into the season — when he has a better idea of whether the Terps will be bowl-eligible — for winter or spring break.
She hasn’t let him forget.
Keihn bought her a phone during his visit, and in the two times they’ve spoken since he left, she asks the same question: “Is everything still in line for your trip?”
“Either six months or eight months,” Keihn answers. “You’ll definitely see me.”