Lawson of Billerica; Catherine Ann (Masters) Lawson, age 74, died April 23, 2012 after a short illness. She was the beloved wife of Fred Lawson and mother of Zoe Lawson. She led a life dedicated to helping others and lovingly tending her gardens. Services were private. Donations to WBUR radio or the planting of a tree or flowering bush may be made in her memory. A celebration of her life will be held in June, near her birthday, June 29.