The X Factor judge's London home was broken into by an armed woman on Saturday night (March 24).
Leanne Zaloumis, who was allegedly armed with a broken brick, was charged with aggravated burglary, and appeared at West London Magistrates' Court earlier this week.
Sinitta has said she is concerned that a crazed fan may end up murdering Cowell in the future if he doesn't move or improve his security.
"Simon has to come to terms with looking after himself properly now he's reached that level of fame," she told The Sun.
"It's a scary thing. Hopefully the intruder didn't want to harm him but they could have. If it had been someone else with an obsession they could have killed him.
"I'm trying to persuade him to move or build a fortress around the house. It was alarming for him, it was like a nightmare. It can't happen again."
Sinitta had previously told Digital Spy that Cowell initially thought that the intruder was her.
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