Counterfactual

The Parallel Lives of Kourtney and Isabella

In 31 girls, Kourtney found its level. 50 years earlier, Isabella occupied that same statistical address.

1964–2025

Kourtney

peak 1990 2025 18801900192019401960198020002020
Peak year 1990
Peak births 646
Latest count 31
Status Endangered
Peak generation Millennial
1880–2025

Isabella

peak 2010 2025 18801900192019401960198020002020
Peak year 2010
Peak births 22,936
Latest count 10,666
Status Declining
Peak generation Gen Z
Kourtney and Isabella peaked in the same cultural weather — the Millennial naming world. They are not replacements; they are siblings separated by 50 years, occupying the same statistical address at different addresses in time.