So in a last-minute move demanded by one of China's highest officials, the two were put together for the Olympic opening ceremony, with one lip-synching "Ode to the Motherland" over the other's singing.
The real singer, 7-year-old Yang Peiyi, with her chubby face and crooked baby teeth, wasn't good looking enough for the ceremony, its chief music director told state-owned Beijing Radio.
So the pigtailed Lin Miaoke, a veteran of television ads, mouthed the words with a pixie smile for a stadium of 91,000 and a worldwide TV audience. "I felt so beautiful in my red dress," the tiny 9-year-old told the China Daily newspaper.
Peiyi later told China Central Television that just having her voice used was an honor.
It was the latest example of the lengths the image-obsessed China is taking to create a perfect Summer Games.
In a brief phone interview with AP Television News on Tuesday night, the music director, Chen Qigang, said he spoke about the switch with Beijing Radio "to come out with the truth."
"The little girl is a magnificent singer," Chen said. "She doesn't deserve to be hidden." He said the ceremony's director, film director Zhang Yimou, knew of the change. He declined to speak further about it.
China has been eager to present a flawless Olympics face to the world, shooing thousands of migrant workers from the city and shutting down any sign of protest.
The country's quest for perfection apparently includes its children.
A member of China's Politburo asked for the last-minute change during a live rehearsal shortly before the ceremony, Chen said in the Beijing Radio interview, posted online Sunday night. He didn't name the official.
During the live rehearsal, the Politburo member said Miaoke's voice "must change," Chen said.
"We had to make that choice. It was fair both for Lin Miaoke and Yang Peiyi," Chen told Beijing Radio. "We combined the perfect voice and the perfect performance."
"The audience will understand that it's in the national interest," Chen added.
He said he felt a responsibility to explain to the country what happened but on Tuesday the link to the video on the Beijing Radio Web site no longer worked.
Miaoke's performance Friday night, like the ceremony itself, was an immediate hit. "Nine-year-old Lin Miaoke becomes instant star with patriotic song," the China Daily newspaper headline said.
Zhang, China's most famous film director, was asked at a post-ceremony news conference about the little girl who swung on wires high above the Bird's Nest National Stadium during the performance.
"She is a lovely girl and she sings well," Zhang said, according to a transcript posted on the Beijing organizing committee's web site.
The switch became a hot topic among Chinese and raced across the country's blogosphere.
"The organizers really messed up on this one," Luo Shaoyang, 34, a retail worker in Beijing, said Tuesday. "This is like a voiceover for a cartoon character. Why couldn't they pick a kid who is both cute and a good singer? This damages the reputation of both kids for their future, especially the one lip-synching. Now everyone knows she's a fraud, who cares if she's cute?"
Others disagreed.
"They want the best-looking people to represent the face of China. I don't blame the organizers for picking a prettier-looking kid over the not-so-pretty one," said Xia Xiaotao, 30, an engineer.
"It's the unfortunate reality that these sort of things turn political," said marketing worker Zhang Xinyi, 22.
It was not the first time an Olympics opening ceremony involved lip-synching.
At the 2006 Winter Games in Turin, Luciano Pavarotti's performance was prerecorded. The maestro who conducted the aria, Leone Magiera, said this year that the bitter cold made a live performance impossible for Pavarotti, who was in severe pain months before his cancer diagnosis. Pavarotti died in 2007 at age 71.
Also Tuesday, Beijing organizers confirmed that some of the opening ceremony's fireworks display - 29 gigantic footprints shown "walking" toward the National Stadium - featured prerecorded footage. The footage was provided to broadcasters "for convenience and theatrical effects," said Wang Wei, vice president of the Beijing Olympic organizing committee.
(American broadcaster NBC also has augmented its Olympic coverage in the past to set the right mood. That fire in the studio fireplace during the 2002 Salt Lake Games? It was just a video.)
Neither of the two little girls involved could be reached by The Associated Press on Tuesday, and it was not clear how the ceremony - or the controversy - might change their lives.
Peiyi is a first-grader at the Primary School affiliated with Peking University. Her tutor, Wang Liping, wrote in her blog that Peiyi is both cute and well-behaved, with a love for Peking opera.
"She doesn't like to show off. She's easygoing," Wang wrote. She and other school officials couldn't be reached Tuesday.
Miaoke, however, was a minor celebrity even before the opening ceremony. The third-grader appeared in a TV ad last year with China's biggest gold medal hope, hurdling champion Liu Xiang, and she was in an Olympics ad earlier this year, China Daily reported.
Her father, Lin Hui, told China Daily he learned Miaoke would be "singing" only 15 minutes before the opening ceremony began.
Lin "still cannot believe his daughter has become an international singing sensation," the report said.