Sister Elizabeth Rickle, a member of the Holy Union Sisters and a retired parochial school teacher, died of pulmonary disease Friday at St. Elizabeth Nursing Home in Southwest Baltimore. She was 90.

Rita Elizabeth Rickle was born in Baltimore and raised on Riggs Avenue. She attended St. Edward's Parochial School and was a 1936 graduate of Seton High School.

She entered a Roman Catholic religious community, the Holy Union Sisters, in Fall River, Mass., in 1936 and initially took the name Sister Frances Louise. She earned a bachelor's degree at Stonehill College in North Easton, Mass.

She later took the name Sister Elizabeth and taught for 40 years at schools including St. William of York Parochial School in Ten Hills. She also held posts in New York City and was superior at St. Peter's Convent in Point Pleasant, N.J., and was on the faculty at St. Francis de Sales School in New York City.

She returned to Baltimore and worked at Caritas House, an assisted-living residence. She retired several years ago.

In retirement, she wrote numerous cards and letters for happy and sad occasions.

"She considered her letter-writing a ministry," said a colleague, Sister Marilyn Spellman of Baltimore. "She wanted people to know that somebody cares."

A Mass was offered Monday at St. William of York Church.

Survivors include a brother, Thomas J. Rickle of Owings Mills; and nieces and nephews.