By the summer of 1689, Peter, then age 17, planned to take power from his half-sister Sophia, whose position had been weakened by two unsuccessful Crimean campaigns against the Crimean Khanate in an attempt to stop devastating Crimean Tatar raids into Russia's southern lands. When she learned of his designs, Sophia conspired with some leaders of the Streltsy, who continually aroused disorder and dissent. Peter, warned by others from the Streltsy, escaped in the middle of the night to the impenetrable monastery of Troitse-Sergiyeva Lavra; there he slowly gathered adherents who perceived he would win the power struggle. Sophia was eventually overthrown, with Peter I and Ivan V continuing to act as co-tsars. Peter forced Sophia to enter a convent, where she gave up her name and her position as a member of the royal family.