After speculation that little Ali Lohan had breast augmentation exploded on the net, big sis Lindsay took to her MySpace Celebrity blog to nix reports that her singin' teen sibling has had any work done. Here's Ali with mom Dina six months ago. Click here to see Ali now.

"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," wrote LiLo. "I am not judging people that do, but I am just saying that it's not something that my family finds necessary to do, especially when you're not even fully developed yet!"

Lindsay -- who is getting ready to reprise her guest role on "Ugly Betty" -- describes an incident where a photog asked her about Ali's "implants," to which she retorted, "Did you really just ask me that? She is a 14-year-old girl, and you are a pedophile!"

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