From the young are of twelve Mother Teresa felt the call of God on her life. She knew she was going to be a missionary, so at the age of eighteen she left home and joined the Sisters of Loreto and took the vow three years later to become a nun. She knew she was set apart, and that God had called her. She began her missionary work for the poor in 1948. She continued for several years until her health started to decline. She stepped down from being the head of Missionaries of Charity in March of 1997 and later passed away in September of 1997.