"You know I've been monitored and in touch with my doctors this whole process," Blair told Farber. "I had these MRIs. The results came back and it all just adds up to that I can't go on with the competition. I pushed as far as I could."
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Blair explained that if she continued, she would risk extensive damage to her body, but vowed to use it as a learning experience for her 11-year-old son Arthur, telling Farber, "I'll have to settle in and get back to being a mom and showing him I have to pull back on something that I love doing and sometimes you make hard decisions."
Not to be deterred, however, Blair said, "I really want to have one last beautiful dance with you."
And that's exactly what she did.
Set to "What the World Needs Now," Blair and Farber danced a gorgeous waltz that brought the ballroom to its feet and practically every person inside the ballroom reaching for the nearest tissue.
"It's so hard for me to take care because I don't want to. I want to be here," Blair told co-host Alfonso Ribeiro after the dance. "But I know, as a mom and as someone who wants to represent people that are taking chances, sometimes there are just consequences to any chance you take, and mine is fine. I'm going to be OK."
After receiving honorary 10s across the board from the "Dancing With the Stars" judging panel, Blair and Farber made their way back down the ballroom floor, where they were surrounded by the other celebrities and professional dancers, as well as Blair's son.
Once there, Blair gave her final send-off.
"This competition showed me how much I love to be around people who are trying their hardest," she said through tears. "How much I love to be around music even though I don't have musicality. How much I love to want to do something again."
There's not much time to recover, as "Dancing With the Stars" returns for Prom Night on Tuesday Oct. 18 at 8 p.m. on Disney+. The scores from the Oct. 17 episode will be combined with the scores from Tuesday night to determine who gets sent home.