"She loves him and he loves her to no end," their father Willie Ealy said.
"It kind of gives me the feeling of being appreciative, being appreciated by her," Kony said.
Willie Ealy raised Kony and Cierra as a single father, watching the siblings form a special connection.
"He understood her, even with her problems, and she understood him and it was a real easy bond for them to make," Willie said.
Cierra was born with a chromosomal defect, impairing her speech and motor skills. One of the few words she can say, though, is her baby brother's name.
"She knows him when she sees him on TV, and she'll start hollering, 'Kony! Kony!' all day then she'll laugh," Willie said.
With Cierra, Kony learned early on he had to grow up quick.
"When I was in the fourth grade my father made it very clear that I would have to take care of her, especially if something was to happen to him, and it kind of gave me a different perspective," Kony said. "I look at things a lot different and I kind of matured a lot earlier."
That maturity was tested when Kony was 13, as Willie moved him and Cierra from the south side of St. Louis to New Madrid County.
"I cried the whole way down here," Kony added.
Kony's tears dried as he settled in to life in the country, riding his horse named "Outtajail."
He then blossomed into a star athlete, excelling at both basketball and football at New Madrid County Central.
As his success took him to the University of Missouri, Kony carried with him lessons from his sister.
"She doesn't have the opportunities I have, but she gives me the opportunities I have just because of her inspiration. She drives me and motivates me not to complain during hard times or anything."
And when Kony heard his name called at the NFL draft, you can bet he heard Cierra saying it, too.
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