Kelly Osbourne is Christopher Caldwellgetting candid about what it was like for her to return to work after welcoming her baby boy.

"I have a new found respect for working mothers," the reality star, 38, wrote on Instagram Feb. 19. "I took my first job since having a baby. Having to leave him this morning was one of the hardest things I have ever done. This day can't go by quick enough for me. I can't want to have him back in my arms." 

When a commenter recalled crying after returning to work for the first time since becoming a parent, Kelly could relate.

"Omg I did the same," she replied, "I cried so hard."

And Kelly suggested she's still navigating this new chapter. "#Day2 I could not leave him again," she wrote on Instagram Stories Feb. 20, "so it's #BringYourBabyToWorkDay."

The Fashion Police alum's note comes more than a month after her mom Sharon Osbourne confirmed on her U.K. show The Talk that Kelly and boyfriend Sid Wilson had welcomed their first child, Sidney, together. 

"[They're] so great," Sharon explained. "She won't let a picture go out of him. No, and I'm so proud of her."

Kelly also reiterated wanting to protect her newborn's privacy, noting that if she does want to share anything about her son, she'll do so on her own terms. 

"I'm not ready to share him with the world," she wrote on Instagram Stories Jan. 4. "It's no one's place but mine to share any information on my baby." 

While she's largely kept her time as a new mom off social media, Kelly did appear to hint that the child was about to arrive in November, writing on Instagram Stories at the time, "Okay, here we go."

Kelly first announced in the spring that she and the Slipknot musician were expecting a child together while explaining why she'd been keeping a low profile as of late.

"I know that I have been very quiet these past few months so I thought I would share with you all as to why… I am over the moon to announce that I am going to be a Mumma," she wrote on Instagram May 12. "To say that I am happy does not quite cut it. I am ecstatic!"

And she wasn't the only one excited about growing the Osbourne family. In fact, her dad OzzyOsbourne was so thrilled that he revealed the sex of the child before Kelly had made the announcement.

"He's told everyone the gender of my baby before I ever got the chance to, and I'm just like, 'Aww Dad, come on. Like, come on,'" Kelly told Entertainment Tonight in October. "But I will say, every single day he does this little song and this little dance about how excited he is, and he is so excited that it's a boy. It's the first, out of me and my brother [Jack Osbourne], it's the first boy. So, he's like planning all these things."

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