Seeing Lindsay Lohan
's 15-year-old sister Ali Lohan
hanging out at nightclubs has raised some concerns, but according to Lilo, who mom Dina Lohan
called a "genius," it's totally cool! "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,"