Luisa met Simon while attending afternoon tea at The Dorchester hotel on behalf of the Shooting Star Chase charity on Wednesday (1 April).
Former Apprentice contestant Luisa was all smiles in a hot pink dress as she grabbed a photo with new dad Simon, who wore his trademark unbuttoned white shirt.
Captioning the snap, mum-of-one Luisa said: "Met @SimonCowell 2day @SSChospices afternoon tea @TheDorchester fab charity which needs more support & recognition! X."
Shooting Star Chase is a leading children's hospice charity caring for babies, children and young people with life-limiting conditions.
Also in attendance was Britain's Got Talent star Francine Lewis, who managed to have a good catch up with Simon before introducing him to guests ahead of his speech.
Former Made In Chelsea star Hugo Taylor, TOWIE star Gemma Collins and former co-star Amy Childs also showed their support, while pregnant X Factor winner Sam Bailey wowed guests with a vocal performance.
Last week, businesswoman Luisa revealed that she's training to be a helicopter pilot. The 26-year-old reality star, who currently runs her Bakers Toolkit business, took her first lesson at training grounds in Elstree and told fans that she couldn't wait to get studying.
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