The tulips, Sister Helen Prejean jokes, bloom for her birthday. The nun and death penalty abolitionist turned 87 in April. Every year at this time, she returns to DePaul University, where she donated her personal archives in 2011: nearly 45 years of journals, letters, speeches and notes from her work to end capital punishment. That work brought her back to campus Friday for an event marking the 15th anniversary of Illinois abolishing the death penalty.