"I knew right away I had to pull over and help them," said driver Nicole Chamberlain

A Wisconsin bus driver is being hailed as a hero after her quick thinking saved a young pair of siblings from freezing temperatures.

Nicole Chamberlain was driving her bus in Waukesha on Monday morning when she spotted a 6-year-old boy and a 2-year-old girl walking outside in the wind and snow, ABC affiliate WISN reported.

Neither child had a coat, and the girl was wearing only a T-shirt, boots and a diaper in the 18-degree weather.

Video obtained by the outlet shows an audible reaction from those on Chamberlain’s bus after it passes the children walking outside.

“Those little kids are out without any clothes on!” a passenger can be heard saying.

Chamberlain quickly stopped her bus and went outside in order to lead the kids into the warmth of the vehicle.

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“They were headed towards a busy intersection, and I knew there was no school bus stop down there or school, so I knew right away I had to pull over and help them,” she told WISN.

As Chamberlain called them over, she asked the kids why they were outside, and they told her they were looking for their grandmother.

“I said, ‘Come with me, I’m going to put you on the warm bus, and I’ll help you find grandma,’” Chamberlain said. “And so they came with me. I picked them up, put them on my bus, and called the police.”

As they waited for police to arrive, Chamberlain removed her own coat and placed it over the girl’s legs to keep her warm, video shows.

The children’s grandmother arrived on the scene shortly after, and told police the boy had gone outside — with his sister right behind him — while she was in the basement, according to WISN. Authorities are reportedly not recommending any charges.

“I’m just thrilled I was in the right place and right time, but even more thrilled the situation turned out to be even better than what you hear sometimes,” Chamberlain told Fox affiliate WITI. “They went back, they were with a happy family. They were safe. That was most important to me.”