(INSIDE EDITION) -- A kindhearted UPS driver adopted a friendly dog that she met along her route after his owner passed away.

Katie Newhouser, of California, formed a bond with the pit bull, Leo, as he would often greet her during one of her stops in Rancho Cucamonga.

Newhouser said Leo would hop in her truck when she drove into his owner Tina’s condo complex. So when Newhouser found out that Tina had passed away, she wanted to step up and help.

“When I found out that Tina had passed away, I was in shock and disbelief,” Newhouser told InsideEdition.com. “I got to know Tina through Leo. As is the case with many of my customers that I have become friends with, I generally will know the dog’s name before their name."

Tina’s son Cannon, who had adopted Leo when he was just a puppy, was away and Newhouser didn’t want Tina’s mom to have to worry about Leo.

“I let him know that I would take care of Leo until he returned. They had enough to deal with,” Newhouser said.

She took Leo into her home, but said it was very rough for Leo in the beginning because he had been so close to Tina.

“He would whine just before falling asleep at night. I really do feel that he was missing Tina,” Newhouser said.

Eventually, however, Leo began to bond with one of Newhouser’s other dogs, Moose, and that helped him a great deal.

Newhouser said Tina’s family eventually agreed it’d be best for Leo to remain with her permanently as he had already bonded with Newhouser’s five other dogs and seemed happy.

“I feel that this was the best case scenario for him. He knew me already and I feel as though there was a huge bond already between us,” Newhouser said. “He always is the first to greet me at the door when I come home and the one who is always closest to me when I sleep.”

Newhouser said she believes all things happen for a reason and Tina can now know that her best friend is taken care of.