Kelly Osbourne has shared a photo of her baby with Slipknot's Sid Wilson for the very first time, and he's wearing a hilarious outfit that obviously pays homage to his grandfather — a bat costume.

Osbourne and Wilson have kept the details surrounding their child rather private. There were reports that Osbourne had gone into labor this past November [via Page Six], but the baby's birth wasn't confirmed until Sharon Osbourne spilled the beans on The Talk in January, where she also revealed that his name is Sidney.

"She won't let a picture go out of him," Sharon added during the discussion. "And I'm so proud of her."

Several days later, Kelly Osbourne wrote on her Instagram story, "I am not ready to share him with the world. It is no one's place but mine to share any information on my baby."

It seems as though she's ready now, as she posted a photo of baby Sidney on her Instagram, though she didn't write a caption and the comments are disabled, though it's unclear when the picture was taken. Not only is this the world's first time seeing Sidney, but the bat costume seems to be an affectionate reference to Ozzy Osbourne's onstage bat-biting incident in January of 1982.

See the photo below.

READ MORE: Why Ozzy Feels 'Deeply Nervous' About Osbourne Family's New Reality TV Show

"I have a beautiful little baby boy, and he is my reason for living, my reason for getting up in the morning. My whole life revolves around him, and now I understand what the word 'purpose' really means," Kelly Osbourne said of motherhood last month during a conversation on Today With Hoda and Jenna.

"[My mom] absolutely adores him, and so does my dad, My dad and him have a real connection," she continued. "My dad's a sleep talker, he always has been. Now in his sleep, he calls out for Sidney. It's really cute."

Rock Star Kids Then and Now

Photos of famous children of musicians. What are they doing now?

More From Banana 101.5