 In September 1949 , Mirta gave birth to a son , Fidelito , so the couple moved to a larger Havana flat . Castro continued to put himself at risk , staying active in the city 's politics and joining the September 30 Movement , which contained within it both communists and members of the Partido Ortodoxo . The group 's purpose was to oppose the influence of the violent gangs within the university ; despite his promises , Prío had failed to control the situation , instead offering many of their senior members jobs in government ministries . Castro volunteered to deliver a speech for the Movement on November 13 , exposing the government 's secret deals with the gangs and identifying key members . Attracting the attention of the national press , the speech angered the gangs , and Castro fled into hiding , first in the countryside and then in the U.S. Returning to Havana several weeks later , Castro lay low and focused on his university studies , graduating as a Doctor of Law in September 1950 . 
