"I just think that we need to give a big round of applause to my sister for even coming onstage tonight," Donny told the sold-out crowd at the Flamingo Las Vegas after the duo made their entrance to several standing ovations.
"Don't do that—I'm going to have to leave," a teary Marie told the audience. "God bless you all. The way the Osmonds survive is we keep singing and that's what we want to do tonight. I know my son would want that and this show is for him."
"Little did I know I would be relying on my faith, especially as much as I did this past week," she said, before dedicating a song to him.
After Marie's solo performance, before which she told herself to "pull it together," Donny told the audience, "How she got through that I will never know.
"I hope you all appreciate what she's going through tonight. She's a strong woman."
After singing their final song together, "It Takes Two," the duo went out with their traditional sign-off, though Marie was unable to make it through the last line without tearing up: "May God keep you in his tender care 'til he brings us together again."
She's due back onstage tonight.
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