Dr. Opal Lee is celebrating Juneteenth the same way she’s spent much of the last century: by teaching, organizing, and reminding Americans that freedom is bigger than a single day. As the nation marks 161 years since the events that gave rise to the holiday, the 99-year-old activist known as the “Grandmother of Juneteenth” is sharing her story — and her hard-earned wisdom — in her new book, A Committee of One . Part memoir and part guide to community activism, the book arrives five years after Lee stood at the White House as President Joe Biden signed legislation making Juneteenth a federal holiday. The annual observance commemorates June 19, 1865, when Union troops arrived in Galveston, Texas, and announced that enslaved people in the state were free — more than two years after President Abraham Lincoln signed the Emancipation Proclamation. For Lee, the journey to that moment stretched across decades.…