Kelly Osbourne says her mother Sharon is her "best friend" and closest "confidant".
The 30-year-old star paid tribute to her mum on her Instagram account admitting Sharon, 62, is her constant "rock in a hard place" and the best parent a daughter could hope for.
In a post made on her Instagram account on Sunday (15.03.15) - Mother's Day in the UK - she said: "Dear Mumma, when I think about how much I love you I finally understand what impossible feels like as it is beyond impossible for me to put into words just how much I love. You are not just my mother you are my best-friend, my confidant, my teacher, my perfect rock in a hard place, and my hero. Im the luckiest girl in the world because you are my Mum. I know you did not want me to make a fuss because Mothers day falls on a different day here in The U.S however mums like you deserve to be celebrated more than once a year. mums like you deserve to be celebrated everyday! so #HappyMothersday Mumma (sic)"
Kelly - whose dad is rocker Ozzy Osbourne - finished her post by writing: "YOU TURLY ARE THE BEST MOTHER IN THE WORLD! @sharonosbourne (sic)"
Sharon recently showed her love and support for Kelly publicly in the wake of her daughter's decision to quit 'Fashion Police' in protest over her co-host Giuliana Rancic's "outrageously offensive" comments about Zendaya Coleman's dreadlocks during a segment, a joke for which she had to apologise.
Sharon posted on Twitter: @KellyOsbourne, I am so proud of you. You can never be bought. You always wear your heart on your sleeve. #ProudToBeYourMum (sic)"
Kelly had co-hosted the E! series for five years before leaving.