Along with nursing of the orphans, widows and the elderly, the sisters stepped into their Medical Apostolate in 1915 by entering into the government Hospital at Bettiah at the invitation of the then governor of Bihar. They also started their education ministry with the establishment of St Teresa Girls' School at Bettiah in 1937, when it was unimaginable for the Indian parents to send their girl children to school. As the missionary activities took their momentum in 1939 the sisters arrived in Hazaribag to collaborate with the government and to work in Sadar Hospital, Hazaribag. Gradually the missionaries realised that the multiplying activities could no more be handled by them without the help of the native vocations. Hence in 1952 they established Holy Cross Novitiate in Hazaribag. Within a short span of two to three decades the congregation started to flourish. From 1960 the Indian Vicariate was declared as Mission Station. For a decade it continued to be a Mission Station with Mother Angelica Wildhaber as the Mission Superior.