LAWRENCE — Anna Sullivan, in one of her last visits with family, held hands with baby Isaiah, her 10-month-old great grandson. Anna Ruth (Abate) SullivanA short time later, the matriarch and local business pioneer would die peacefully in her sleep at age 97. Officially, Anna was mother to four, grandmother to nine and great grandmother to one.But throughout the Merrimack Valley, she was regarded as a maternal figure, professional leader and role model to so many more.She “exemplified a loving mother and a good friend who had the stamina and resilience to balance her home life and her career and to be successful at both important endeavors,” said Pamela Driscoll of Lawrence, a longtime worker at the T.A. Sullivan Insurance and Real Estate Agency.Widowed unexpectedly in 1970 at age 45, Sullivan went on to run the successful Greater Lawrence insurance and realty business while raising four boys — two of whom would become mayors of Lawrence.“She was just really good at multi-tasking ... an...