HOUSTON -- Lots of people make jokes about cops and doughnuts. Tyler Carach made it his mission.

He stopped in Houston with his mother, Sheena Carach, part of a ten-day road trip for his tenth birthday, thanking cops all over with free doughnuts.

"Thank you, buddy, thank you," one officer told him.

Tyler got the idea back home in Florida. He saw four cops in a store -- and used his allowance to buy them doughnuts.

Tyler Carach with some of the doughnuts he brings to police officers. CBS News

"It makes me happy," Tyler said. "Because I get to thank the person that keeps my family safe."

How many police officers does he want to buy a doughnuts for?

"Every single one in America," Tyler said.

By our count, that's 900,000 cops.

Tyler Carach delivering doughnuts to police officers. CBS News

So far, Tyler has visited 24 states in 14 months. In Las Vegas, he thanked cops and first responders for their heroism after last month's massacre.

In Albuquerque, cops sang his praises -- "Happy birthday," that is.

Tyler's mother taught him to think big. So far, he has handed out 34,000 doughnuts.

Tyler Carach with some of his new officer friends. CBS News

"If you breathe good into the world, if you speak good into the world, if you do good into the world, it does come back to you," Sheena said.

"I get to go and see these grown men and women tear up sometimes and come to me and say, 'You have no idea what this means to us,'" Sheena said.

Just ask Houston officer Thomas Wozniak.

"It makes me prideful for wearing this uniform," Wozniak said. "To see this little boy give so much support and love, that's awesome."

Tyler wants to become a cop himself one day. And then, just maybe, a perfect stranger will buy him a doughnut.