Noah Kirwin and his sister Leah are titanium.
Not literally, of course. In this instance, "titanium" is more of a metaphor for inner strength in the face of adversity. Because as this video of the two singing David Guetta's song of the same name shows, they're wonderfully human, and they sure sing with a lot of heart.
Leah shared the video of the duet on her Facebook page last Saturday, writing, "Thought I'd do a duet with my favourite little man singing his favourite song, Titanium🙈 💖 Enjoy!" Noah is Leah's younger brother and has Down syndrome, according to video licensing company Jukin Media.
The song starts a little slow -- Noah even lets out a yawn as his sister starts strumming the guitar -- but by the time Leah hits the first chorus, there's no stopping him.
Not surprisingly, the video has gone viral, tallying up more than 886,000 views on Facebook.
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