A complaint lodged by the National Labor Relations Board alleges that Steward Health Care System unlawfully fired a nurse at its Holy Family Hospital in Methuen in August for leading a union organizing drive, in a case that underscores the deterioration of once-warm relations between Steward and the Massachusetts Nurses Association. The complaint, issued Dec. 29, also cited Steward for preventing other Holy Family nurses from wearing buttons during the summer in support of the fired nurse, Mary Ramirez, 61, a 40-year nursing veteran who worked at Holy Family for 18 years.
