Kelly Osbourne says leaving her son 'was one of the hardest things I have ever done'

Kelly Osbourne has shared her difficult decision to return to work after giving birth to her son, saying it was "one of the hardest things" she has ever done.

The 38-year-old welcomed her first child with her partner Sid Wilson in November last year and revealed she has just completed "Day 1 of filming" a new project.

Taking to Instagram on Sunday, Kelly shared a selfie with her makeup artist Kip Zachary as she announced her return to work.

"I have a new found respect for working mothers. 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.

Kelly shared a fun snap with her makeup artist (kellyosbourne/Instagram)

She recently welcomed her first child (@kellyosbourne/INSTAGRAM)

"This day can’t go by quick enough for me. I can’t want to have him back in my arms," she wrote.

She also shared a picture of the camera crew on her Instagram Story, giving fans a glimpse at her mystery project.

Kelly's fans offered words of encouragement as she opened up about her work woes.

One person commented: "You got this mama!!! It is not easy but you are so strong and I am sooo proud of you! I love you!!!!!"

Kelly shares her son with partner Sid (Instagram)

She said it's been difficult to return to work (Getty Images,)

Another wrote: "Yes to all of this! It’s extremely difficult all around. You got this," while a third simply added: "Best mommy!"

"I cried my first day back at work. I felt so bad for leaving him; but it gets better. Congratulations on the birth of you little boy," another fan encouraged.

Another agreed: "Awwww it’s so hard at first, does it get easier? No but you get better at not letting the mom guilt take over and look forward to the joys of returning home. You’ve got this!!"

Kelly's mother Sharon Osbourne was the one who announced her grandson's unusual name.

Appearing on TalkTV last month, 70-year-old Sharon was asked if she ever takes up grandparent duties and looks after her grandson, as she replied: "Yes, Sydney."

"They're doing just so great. So great. She won't let a picture go out of him and I'm so proud of her," she added.

Kelly revealed she was expecting her first child in May last year, announcing the happy news on social media.

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