A two-year-old toddler, Isla McNabb, from Kentucky, United States became the youngest ever member of Mensa, which is the largest and oldest high IQ society in the world. Mensa International is a non-profit organisation open to people who score at the 98th percentile or higher on a standardised, supervised IQ or other approved intelligence test. A report said that McNabb tested in the 99th percentile for the Stanford-Binet Intelligence Scales.