According to the New York Daily News, on one occasion Mr Cardoso turned up to the fourth floor of the Tribeca office where Ms Obama was working as an intern and asked the eldest Obama child to marry him.
Sources told the paper that the Secret Service also stopped Mr Cardoso when he tried to follow the former first daughter out of a building in the West Village where she was doing another internship. The agents reportedly recognised the man and ordered him to leave the eldest Obama child alone.
Agents are then said to have gone to Mr Cardoso's Brooklyn apartment and interviewed him, concluding that he had psychiatric issues and taking him to a Brooklyn hospital to be evaluated.
Sources told the paper the Secret Service agents reported Mr Cardoso to the police on Tuesday.
Ms Obama recently gained global attention for joining a protest against the Dakota Access pipeline held at the Sundance Film Festival. She was reported to have left her family’s Caribbean holiday to attend the largest independent film festival in the US back in January.
While Ms Obama has not spoken out about President Donald Trump, her father said her and younger sister, Sasha, were “disappointed” about his victory. Nevertheless, the former President was insistent that they would remain positive and not “mope”.
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