His eldest son from his first marriage, Sheikh Mohammed bin Sultan Al Qasimi (1974–1999), was the crown prince of the emirate and died after a heroin overdose at the Emir's residence in Wych Cross Place, near Forest Row, East Grinstead, on 3 April 1999 at the age of 24 years. A state mourning period in Sharjah of seven days was observed and flags flew at half-mast. With reports of increasing drug abuse problems in the emirate, in May 2018 the emir announced the directive to establish the "Irada" drug addiction treatment and rehabilitation centre in Sharjah.