A West Virginia state trooper who found a baby boy covered in vomit in the backseat of a car during a DUI arrest was reunited with the “little man” on Monday.

Senior Trooper Derek Graham was treated to a surprise visit by one-year-old Travis on Monday at his detachment in Princeton, W.Va., where he was greeted with a “big smile.”

Graham had not seen the baby since last Tuesday, when he and another trooper pulled over a female driver after finding her “disoriented” in a gas station parking lot during rush hour.

After the woman was taken into custody on suspicion of driving under the influence, Graham and his partner went to conduct a “vehicle inventory.”

They discovered the woman’s baby sitting in a car seat, wearing only a diaper.

“He had vomit all over his body, all over his face,” Graham said in an interview with CTVNews.ca. “He smelled like feces and urine and he had a soiled diaper.”

The troopers contacted child protection services to advise them of the situation, and promptly brought him back to their detachment.

Once in Graham’s office, the baby would not stop crying and the troopers noticed he had a “horrible cough.”

Graham, a father of four, said the “dad instinct” took over at that point. He removed the baby’s soiled diaper, put him in a sink and began to bathe him.

“He stopped crying immediately when I washed him off and got him feeling better,” Graham said.

With no diaper or any baby equipment in the office, Graham wrapped the infant up in a clean blanket and “he was my sidekick for the rest of the evening.”

Hours later, child protection services arrived to place the baby with a guardian.

On Monday, not a full week after the incident, Graham was called into the lobby of his office not knowing that the baby’s legal guardian had brought him to visit and say thank you.

The first thing he saw was “that big smile staring back at me,” Graham said, calling the reunion with the baby “emotional.”

It wasn’t until Monday that Graham learned Travis’ name. During the arrest last week, the mother was apparently unable to speak her child’s name.

In addition to learning his name, Graham also found out that Travis had croup, which explained why the child had such a bad cough.

Graham said that he was glad to see Travis again, and has good memories of his time with the baby, who he dubbed “the little man.”

“It was a bad day that turned out to be a good day,” he said.