Mischa Barton's Doggie Days

Barely legal Mischa Barton spends some down time with her pet pooch at a local dog park in L.A. on Tuesday afternoon. Mischa‘s sister, Hania, was recently checked into rehab to treat her addiction to prescription painkillers.

Note: This is the answer to the latest installment of “Celebrity Guess Who?”
Congrats, anony, who answered it ridiculously fast!