Kentucky toddler, 2, is the youngest Mensa member in US

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CRESTWOOD, Ky. – Just after Isla McNabb's second birthday, Jason and Amanda McNabb found their  home littered with letters – little plastic alphabet letters, to be precise.

They were everywhere. In front of the chair, the letters spelled out "c-h-a-i-r." On the icemaker, magnetic letters said "i-c-e." Even the family feline wasn't spared, the letters "c-a-t" found resting next to her.

In the kitchen, Amanda looked down and found "m-o-m" spelled out next to her.

Jason described the experience as "almost a little creepy." Amanda found it adorable.

Their toddler, Isla, was responsible for all of the words. Before this, Jason had spelled words out on a tablet to see if Isla could sound them out. She quickly understood them, and they kept giving her more words to learn.

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Isla's parents always had a hunch their daughter was really smart, but they never expected she would become the youngest member of American Mensa.

Last month, she scored in the 99th percentile of intelligence for her age, earning the girl a spot in the prestigious international high intelligence organization.

Founded in England in 1946, Mensa has about 145,000 members from more than 90 countries. More than a third of those members – about 50,000 – come from the USA.

Isla reads whatever she can get her hands on – even sounding out scribbled questions in a reporter's notebook.

"It started right when we brought her home from the hospital. If we had something on TV, she would watch it. She would be fixated on it, not looking around like other babies. She would be focused on it," Jason said.

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Isla is the fourth child in Jason and Amanda's family, but they've noticed her developing at a more rapid pace than the other children. 

Jason, a dentist, was a gifted child himself. When he was in second grade, he took an IQ test that would have qualified for Mensa, he said, but he never joined the organization.

A visit to a child psychologist 

Amanda came into the kitchen to see a cardboard box with the word "Mom" written on it. She checked the home's security camera, convinced someone must have helped Isla, but the footage showed the child writing by herself.

Soon after, she started memorizing the names of dinosaurs.

“I drew a picture of a stegosaurus, and I thought she would say ‘dinosaur,’ but she was like, ‘stegosaurus,’” Jason said. “So then I drew a picture of a triceratops, and she said ‘ceratops.’ Like, ‘OK, can you start doing our taxes’?”

 The McNabbs wondered whether Isla had a quirk that would go away or if she was truly gifted. They wanted to make sure they properly fostered her intelligence.

They decided to take her to a child psychologist. Many doctors in Louisville refused to conduct an IQ test for a child as young as Isla, but the McNabbs finally got a "yes."

After hearing stories about Isla's reading, writing and spelling abilities, Dr. Edward Amend told them to bring her in. Typically, the Amend Group does not test children under 4. Amend explained that children can be variable and difficult to test. Some days, 3-year-olds may be very engaged, and sometimes they may not be. The testing can take hours, and for small children, this can be tiring and require a lot of breaks.

Amend was impressed by what Amanda and Jason told him, and he made an exception.

In early May, Isla was tested on two days. Jason and Amanda were stunned by the results. Isla scored "superior" in every category and "very superior" in knowledge. She is "hyperlexic," which indicates a precocious ability to read.

'She's new to (Mensa), and we get to watch her grow'

They sent her scores into Mensa, and she was accepted. Amanda's brother wondered if Isla was the youngest member. Jason and Amanda reached out to the organization, and Charles Brown, the director of marketing and communications for Mensa, confirmed it. (There have been other 2-year-olds in the organization, but none younger than Isla at this point.) 

"I wouldn't have believed any of this if it wasn't firsthand," Amanda said. "You see those stories of kids that are playing chess at 3 or learning the periodic table or all of the presidents. People keep asking if we are going to teach her those, but no. She has no interest in it."

They are letting Isla take the reins. 

This has meant buying a lot of alphabet sets and flashcards. For Isla, learning words is like a game.

Gifted people "need one thing, and that is to be challenged," Brown said. "They are just constantly absorbing."

Isla picked up on sign language, surprising her parents by signing the word "stop." Her parents said if they want to keep a secret from Isla, they can't spell it out.

"If we say we are going to get 'i-c-e c-r-e-a-m' she goes, 'ice cream!' We have to text each other if we don't want her to hear," Jason said.

Beyond fostering curiosity and quenching boredom, Amend said, gifted students need time.

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"They need time to be a kid, they need time to be a gifted kid and they need time to be a gifted student," he said. "Those three things don't always overlap, and they may look differently for a gifted kid. Maybe she's biking with her best friend but also talking about chemistry. Maybe she wants to play Ticket to Ride instead of Trouble."

Amend said people would not expect a tennis prodigy to develop on her own, and the same is true for gifted children. They typically need special accommodations. This is why the McNabbs applied for Mensa. 

Amend suggested that gifted youngsters join high intelligence organizations to give them support. He said the National Association for Gifted Children has a number of TIP sheets (Timely Information for Parents).

The McNabbs can talk with parents of other gifted children, and Isla has access to a community of like-minded individuals. When she gets older, the McNabbs plan to connect her with a network of other children in Mensa who live around the area.

"It's just a spark of delight when we get these young kids," Brown said. "They have this creativity and life about them that just makes you go 'wow.' We can't wait to see what Isla does. She's new to us, and we get to watch her grow."

The McNabbs aren't sure what the future may hold for their daughter. They are ready to cultivate her passions and see what she needs as she gets older and goes to school – whether that means skipping grades, joining the gifted program or something else.

They don't plan on telling her what her IQ score is anytime soon.

"We don't want her to develop a complex or feel like she has something to live up to," Amanda said. "She's having fun, right? Let's let her enjoy it."

Follow Eleanor McCrary on Twitter: @ellie_mccrary