What significant event occurred on March 13, 2019?

The significant event that occurred on March 13, 2019, was Pie A Pi. This event typically involves chapters participating in a fun activity where sisters can throw pies at each other as part of a fundraising effort or to promote sisterhood and engagement within the chapter. It's an opportunity for members to bond and create memorable experiences, reinforcing the sense of community within the organization.

The other events listed, such as Founders Day Celebration, Recruitment Week, and Sisterhood Retreat, play essential roles in the sorority's annual activities. However, they do not specifically relate to the importance or the specific date mentioned in this question. Founders Day is generally celebrated on a different date to honor the organization’s legacy and founders, Recruitment Week is a planned timeframe for bringing in new members, and Sisterhood Retreats serve to deepen the bonds among sisters but do not typically align with the March 13th date.