The parents of the 10-year-old schoolgirl crowned this year's Child Genius have been criticised after her place in the final was secured by her mother.
Rhea, from west London, spelled the word "eleemosynary", to beat nine-year-old Saffy to the 2016 title.
She clinched her final spot when her mother Sonal - who gave up her job as an obstetrician to help educate Rhea - intervened in a previous round.
Sonal queried why an answer Rhea had given during her specialist subject round, on Florence Nightingale and the founder of modern nursing's influence on military and healthcare reform, had been deemed incorrect.
Independent adjudicator Olivia van der Werff agreed that the question had been too general and accepted Rhea's answer, giving her an extra point.
It meant that Rhea avoided a tie-break with Birmingham-born Stephen, going head-to-head with Saffy, from Egham in Surrey, in the final instead.
Viewers were flabbergasted as the girls rapidly calculated sums such as "14 times 3, minus 16, times 3, divided by 2, plus 44´´, and answered questions on everything from the nationality of composer Gustav Holst to the year the American Constitution was approved by Congress.
Rhea was crowned winner when, with the pair on nine points each, she correctly spelled eleemosynary, meaning charitable.
A victorious Rhea said all the hard work had been worth it.
"It's meant getting up early, going to sleep late, studying," she said after four weeks of gruelling competition on the Channel 4 show.
"It just feels really, really great."
But her parents were criticised by viewers, who accused them of being pushy.
Others rallied to the defence of the family, who moved to Britain from the US six years ago.
Some criticised the show, hosted by Richard Osman.