how does the president's wife die in independence day
Due to injuries from the alien attack.
Independence Day (1996 film)
 Meanwhile, Steven's fiancée Jasmine Dubrow and her son, having survived the destruction of Los Angeles, rescue other survivors, including the critically injured First Lady, Marilyn. Though they are later found by Steven and taken to Area 51, Marilyn dies shortly after being reunited with her family.
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Independence Day (1996 film) [SEP] Plot
It uses Okun's vocal cords to communicate before launching a psychic attack against Whitmore. After Secret Service agents and military personnel kill the alien, Whitmore reveals what he learned when they were linked: the invaders plan to strip Earth of natural resources. He reluctantly authorizes a nuclear attack against one warship situated above Houston as a trial, but it remains intact. Meanwhile, Steven's fiancée Jasmine Dubrow and her son, having survived the destruction of Los Angeles, rescue other survivors, including the critically injured First Lady, Marilyn. Though they are later found by Steven and taken to Area 51, Marilyn dies shortly after being reunited with her family.