Against the background of Cold War tension and Marian devotion, the Chicago province functioned under the watch of Mother Mary Felicitas Kruczkowska. A provincial councilor since 1932, Mother Felicitas had accompanied Mother Jolanta to Mexico to survey the Santa Rosa Colony before missioning sisters there.
Following World War II, she governed the province with the approach of a businesswoman. The Chicago Felicians benefited from her rigor with enhanced teaching skills and reputation. The same attention was bestowed on the nursing apostolate, emphasizing performance excellence.
With interest in territory west of the Mississippi, Mother Felicitas opened several schools and a hospital there. In 1938, 10 sisters arrived in Pomona, California to staff St. Joseph Elementary School. Three Felicians arrived in Panna Maria, Texas, in 1946. In 1949, Pomona Catholic opened with three sisters, and two more staffed Sacred Heart School in Pomona.
In 1948, Mother Felicitas and her council signed a contract to operate Rosary Hospital in Corning, Iowa. In addition, they took charge of the new St. Andrew Bobola Home in Niles, Illinois, and staffed Our Lady of the Gardens, a parish serving Altgeld Gardens, a government housing project built for African American veterans of World War II.
During Mother Felicitas' administration, the sisters observed both the 50th anniversary of the Foundress’ death and the 125th anniversary of her birth in 1949 and 1950, respectively.
The Chicago community reached 800 sisters under Mother Felicitas, which resulted in the division of the province and the creation of Assumption of the Blessed Virgin Mary Province in Ponca City, Oklahoma.