Kelly Osbourne First Birthday Without Ozzy, Celebrates With Sharon and Family

Kelly Osbourne rang in her 41st birthday -- her first without dad Ozzy Osbourne -- with family at Los Angeles' historic Chateau Marmont.

Check out the clip of her heading into the posh hotel ... she appears to be in high spirits as she holds her nearly 3-year-old son, Sidney, close on her hip while her Slipknot DJ fiancé Sid Wilson gets their stroller together.

She showed off her frame in a fitted black dress and drew attention to her famous cheekbones by putting her platinum blonde hair in a ponytail.

The "Fashion Police" alum was joined by her family -- including mom Sharon and brother Jack -- for her special night out. She was also joined by close friends Daniel Nguyen, Jeff Beacher and Shanina Shaik.

As we mentioned, Kelly celebrated her first birthday without her father Monday ... and he was on her mind as she paid tribute to him just before she turned 41 by sharing snaps of them together over the years.

She reflected, in part ... "Tomorrow is going to be a first for me. The first birthday without my dad. Every year the thing I look forwarded to the most was spending the day with him and the cards he would write me. Knowing that I will never get one again shatters my heart."

As you know, the Black Sabbath rocker died on July 22 at age 76 from a heart attack.

Kelly previously said losing her father was the hardest thing she's gone through.