A stylist, make-up artist, fashion designer and songwriter, Sabrina Kouider is originally from Troyes, in north-eastern France.
Nanny verdict: Sabrina Kouider 'fixated with her ex-boyfriend' Mark Walton
Ms Kouider, who is 35, is of French Algerian descent and is estranged from her French husband.
During the trial the jury heard how she was fixated with her ex-boyfriend Mark Walton.
Walton, a founding member of the world famous band Boyzone, lives in LA and is now a judge on the talent show Pop Idol in Vietnam.
Sabrina Kouider was fixated with her ex-boyfriend and harboured "outlandish" delusions that he was in contact with Sophie and the pair were colluding against her.
The mother-of-two created a fantasy world casting Mr Walton as an evil villain who had seduced Miss Lionnet with sex and promises of Hollywood stardom. In truth Mark Walton had never met or even heard of the au pair.
Sabrina and Mark Walton split up after two years together and in that time, Kouider had reported Walton to police more than 30 times and received a caution for branding him a paedophile on a fake Facebook profile.
She also accused him of sexually abusing a cat, using black magic and hiring a helicopter to spy on her.
Giving evidence, LA-based Mr Walton admitted he had been "in love" with Kouider but said she would "flip" and go "crazy" for no reason.
"She would go from the quiet softly spoken with a French accent, to someone who would flip, who would be very angry and loud, it didn't matter where, she would go crazy."
Kouider's co-accused, banker Ouisemm Medouni became an ardent believer in her twisted reality and they interrogated Miss Lionnet for hours to get to "the truth".
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