Lindsay Lohan urges her sister to away from clubs

Lindsay Lohan has advised her younger sister Ali to stay away from the clubs -- and urged her to "keep her head on straight."

"Stay away from the clubs!" Lindsay, 21, tells Extra in a new interview about 14-year-old Ali -- who is set to be featured on mom Dina's new E! reality show.

Ali has previously spoken of her desire to follow in Lindsay's footsteps -- she told Teen Vogue last month: "I grew up watching Lindsay. It made me want to do what she does.

"Just the whole vibe. Being there, being on camera, or on stage, with everybody listening to you ... it's so cool when people look up to you.

"I've already been asked for my autograph and it's just a really good feeling to have."

"I want it [be famous] so bad. So bad you don't even know. And now, it's actually happening."

And Lindsay - who has been arrested twice for DUI and completed three stints in rehab - says she's now gearing up to re-launch her own career.

"I’m part of a film that Jack Black is involved in that is starting around April, hopefully," says Lindsay. "We’re getting the cast together now."

The 'Mean Girls' actress' icon Ann-Margret "is a part of it," Lindsay adds. "I'm very excited! I just really respect her."

Lindsay — who recently went topless in New York magazine — is also keeping busy with a new album.

"It’s more of a dance vibe," says Lindsay, who is collaborating with Ne-Yo on the album. "This one I do want to tour with."