Two brothers saved for years to buy their mom a very special Christmas present this year: her dream car.

Daniel Knust of Wollongong, Australia, just south of Sydney, posted a video of the moment he and his brother, Jason, presented their mom, Carol, with a BMW 3 Series.

"Showing gratitude to our beautiful Mum who's worked so hard to give us everything in life," he wrote on Instagram. "Compared to the sacrifices she has made for us over the years, this is nothing."

Knust, 30, told TODAY the surprise had been in the works for years.

"My mother first said about 10 years ago that she wanted a BMW, and we never forgot that," he said. "We said that one day we would get her one and we've been saving up for it."

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He and his older brother saved for about five years before they bought the car.

"We put aside a little each week knowing one day we would be able to get her (the car)," Knust said.

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In the video, taken by Knust's wife, their mother appears shocked, saying "no" over and over as the brothers walk her to the garage to find a silver BMW with a big red bow.

"She was just very surprised and couldn't believe it," he said. "She absolutely loved it."

The car will replace their mom's current ride, a Toyota Corolla. They gave her the car as an early Christmas gift, but also as a way to say thank you.

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"She brought us up on her own and worked two jobs for most of her life to keep my brother and me in school and give us everything we needed," Knust said. "We watched her go from her full-time job on a Friday, come home, shower, go start another job and work the weekend at a restaurant."

He added: "We just thought it would be nice to show how grateful we are for everything."