Lohan`s mistakes teaching her younger sister

London: Troubled actress Lindsay Lohan thinks that her younger sister Ali has learned `what not to do` by watching her mistakes.

Lohan, who has been to rehabilitation centre three times and was recently sentenced to three years probation for stealing a necklace, has admitted that she has made so many mistakes in the past, that it has deterred Ali, 17, from behaving badly. "She`s seen a lot of stuff that I`ve experienced and she knows exactly what not to do. So she kind of knows better through watching me," contact music.com quoted the 24-year-old as saying. However, Lohan is not worried about her younger sister being attracted to Hollywood vices and thinks she is "tougher" than the actress herself. "She`s tougher than I am. She has a good head on her shoulders. Maybe it was different for me because I didn`t know what to expect and it just happened really fast. I didn`t have a big sister. If I`m going out late, she`ll go home early," Lohan said. IANS