Lindsay Lohan proved to be a very protective older sister promptly fighting back rumors that her 14-year-old sister Ali got a boob job.

Speaking on Ali's behalf, Lindsay took on the series of online reports, which suggested the aspiring singer and reality show star underwent breast augmentation surgery after USmagazine.com posted side by side comparison photos of Ali's chest, in which she looks to have grown breasts overnight.

"i just had to share something that came up today and it made me feel a bit sick to my stomach. so, here's the visual...two paparazzi come up out of nowhere (like usual) and start throwing questions at me...one of them being, 'Hey Lindsay, what do you have to say about people commenting on your sisters implants?' WOW!!!!!!!!!!!!!!!!!!!!!!!!" Lindsay wrote on her MySpace blog.

The 22-year-old actress, who's making headlines on her own refusing to discuss her supposedly romantic relationship with DJ Samantha Ronson, said she was shocked by the photographer's question, replying "Did you really just ask me that? She is a 14-year-old girl, and you are a pedophile!"

In the two pictures, taken three months apart, Ali's chest does seem to have taken considerable proportions. She was most recently spotted flaunting new curves at a Jonas Brothers concert in East Hampton, NY on August 9.

In the past, Ali denied a rumored nose job, and she will most likely say she did not have anything done to her chest, either.

Lindsay herself is widely believed to have had a boob job at 17, which she is thought to have had reduced.

"All i am trying to say is, is that, i was raised with a wonderful family surrounding me, of course we have our ups and downs, but all in all my mother taught us to appreciate what we have been given. Nor would she ever encourage, or allow a 14 year old child to alter her body," Lindsay carried on explaining, adding that she does not judge people who do get plastic surgery.

Still, the "Mean Girls" star know what it’s like to be young and famous and continued defending her younger sister reminding people Ali is still just a teenager.

"It is hard enough being 14 years old and you have enough insecurities to begin with, then add being in the public eye…," she wrote. "I just find it really disconcerting that people have to focus on the negative and that some people are sooooo bored with their own lives that they need to manifest lies to hurt another person."

Ali Lohan said in an interview for Teen Vogue earlier this year that she wants to be famous just like Lindsay.

"I want it so bad," Ali told the mag. "So bad you don't even know. And now, it's actually happening. I've already been asked for my autograph, and it's just a really good feeling to have."

Her mom Dina, with whom Ali stars in an E! Channel reality series "Living Lohan" claims she is just helping her daughter fulfill her dream to be a singer, that she is not a "stage mother" and is not pushing her into show business.