No, leap year doesn’t always happen every 4 years: VERIFY
WKYC: Aviva Rothman, associate professor of history at the College of Arts and Sciences, noted that the point of leap year—that extra day at the end of February every four years—is to keep our calendars synced up with the seasons. But over time, even adding an extra day every four years isn’t quite enough to keep our weather on that track, she said.