Opal Lee, a retired Texas teacher known for her activism and as the "Grandmother of Juneteenth," turned 100 on Wednesday.

A celebration honoring her decades of advocacy was held at the National Juneteenth Museum in Fort Worth, Texas.

As part of its Uniting Voices Speaker Series, the National Juneteenth Museum hosted "A Conversation with Michelle Obama," with the former first lady leading the celebration of Lee's extraordinary legacy while looking ahead to the future she has worked for decades to make possible.