Kelly Osbourne Throws Spooky Bash for Son Sidney's First Birthday: 'Greatest Joy I Have Ever Felt'

The reality star shares her baby boy with Slipknot rocker boyfriend Sid Wilson

Kelly Osbourne is full of all the mom feelings as her little boy celebrates his first birthday.

On Monday, the 39-year-old shared a heartfelt post reflecting on son Sidney, whom she shares with Slipknot musician Sid Wilson, as he turns one.

"This past year has been the most magical year of my life for one reason. That reason is you baby Sidney. To watch you grow, learn and become a little man is the greatest joy I have ever felt," the new mom wrote.

"The most magical bond I have ever experienced is the bond I feel with you. Before you, love was just a word that I thought I understood. NOW I truly understand what love is," she continued. "I am forever indebted to you for teaching me the beauty meaning and truth of love. What more can I say other than I love you."

"Happy birthday sweet [prince]. We made it on our first trip around the sun together. 💜💜💜💜💜💜💜💜💜💜💜💜."

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Related: The Osbournes Pose with Kelly and Jack's Babies as They Celebrate the 'Best Halloween Ever'

Over the weekend, the former Fashion Police host also shared scenes from Sidney's birthday party, a black-and-white spooky celebration shared with friends and family.

Adorable ghosts decorated the black and white tiered cake as kids played in a padded outdoor area with different drums and toys for all kinds of fun.

Osbourne held her baby boy in sweet photos with longtime friend Don Deluca shared on Instagram, where he wrote, "Happy Birthday to the prince. Sid Jr 🤘🏼🤘🏼🤘🏼🤘🏼❤️❤️❤️ First birthday rager."

Speaking on the first episode of the second season of The Osbournes podcast, the new mom celebrated her little boy's budding personality.

"He's gonna be such a naughty little boy," Osbourne squealed, delighted. "He's funny. It's weird to me how I look at him and he's like 18 weeks old and he does things that are just really funny."

She was also happy to share that Sid "he loves his nana," Sharon Osbourne, 70. "He goes and sees nana every morning and every night before bed and he just sits there laughing and chuckling."

"I do silly voices for him and he just loves it," Sharon explained. "He's very smiley with me."

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