Dani Dyer finds it "scary" her 11-year-old sister Sunnie thinks she is "overweight".
The 'Love Island' winner - who is the daughter of actor Danny Dyer - has been left worried after seeing pictures of her younger sibling with her face scribbled out, and thinks social media pressures make things "so much worse".
Writing in her book 'What Would Dani Do?', she said: "Now with social media, it's all so much worse for people.
"I worry about my sister Sunnie - she's only 11 and already thinks she's overweight.
"I have to keep an eye on her to make sure she's looking after herself because sometimes she will show me a picture from Instagram and she's scribbled her face out because she doesn't think she looks very nice. She's beautiful."
Dani also claimed people's pictures on the photo-sharing site are "all fake".
She added: "So don't ever compare yourself and don't spend too long on there either.
"Your real life is much more important than this pretend world where everyone looks like they have no facial features because they have Facetuned themselves so much."
Dani - who also has five-year-old brother Artie - has been "upset" by online haters who have told her she looks "pregnant" and "bloated" in the past because "they were such nasty things to say".
The TV star won last year's 'Love Island', with then-boyfriend Jack Fincham, but they recently split.
In a statement on Instagram, Jack wrote: "There is no easy way to say this and it isn't going to be an easy time but me and Dani are not in a relationship anymore.
"We will always care a lot for each other and have love for each other and I mean that from the bottom of my heart and I wish her nothing but happiness.
"We have some amazing memories together and have been through a lot but sometimes things aren't meant to be and we really did try to make it work but it unfortunately didn't and that is life."
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