The big day for the littlest member of the family -- June 15 -- happens to fall on Father's Day this year.
A source told E! News the family plans to have a quiet celebration of both events Sunday in New York City before holding a larger birthday celebration next weekend.
"This weekend, Kanye is performing at Bonaroo and they will fly to New York City for a low-key Father's Day and birthday party," the source said. "They are throwing her a big party next weekend and Kourtney [Kardashian], Khloé Kardashian and kids coming home for it."