Hattie McDermott is on the move! Tori Spelling and husband Dean McDermott celebrated daughter Hattie's first birthday last October in an Alice in Wonderland-themed bash held in the front yard of their L.A. home.

Looking absolutely adorable in a rainbow tutu, polka-dot tights and silver ballet flats, Hattie made sure to hold the crowd's rapt attention with a big moment: Walking her first steps at 12 months! "Our birthday girl surprised all of us by hitting a huge milestone!" the actress and designer, 39, wrote in her blog -- and Us Weekly has the first look.

As Hattie's friends and family (including grandmother Candy Spelling and siblings Liam, 6, Stella, 4, and baby Finn, 8 months) played with balloon makers, face-painters and more, the little tot, without warning, stands on her own for the very first time -- then walking as her mom looks on incredulously.

Her mother and grandmother then lead her inside the family home where dad McDermott, 46, marvels at his little girl.

"Hattie just took her first steps!" a tearful Tori says on camera, noting that she's the youngest in the brood to get moving. "You win!"

Watch Hattie's surprise first steps -- and her mother's emotional reaction -- in this first-look clip now!