Lindsay Lohan: 'Sister Ali never had plastic surgery'

Lindsay Lohan has denied allegations that her younger sister Ali has had plastic surgery.

Ali, 17, was spotted in Beverly Hills earlier this week with more prominent cheekbones and a significantly thinner frame, leading to speculation that she had gone under the knife.

However, Lindsay shot down the reports, saying that her sister would not take such measures with her body.

"She has never," Lindsay told E! News.

In addition, a source told the website: "Ali just lost a lot of weight."

Meanwhile, the girls' father Michael Lohan confessed that he is concerned by Ali's new look.

"It's scary to see my daughter looking like this," Michael told Radar Online. "Ali was always on the thin side, but seeing how much weight she's lost there appears to be a drastic change that concerns me."

He continued: "This industry has a way of having a harmful effect on one's health and well-being. To see what Lindsay has gone through is one thing, I certainly hope Ali isn't going through the same thing."

Last month, Ali signed a multi-year modelling contract with NEXT Model Management.

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