Miley Cyrus' 13-year-old sister has hit back at her critics after shaving the side of her head.

The 'We Can't Stop' hitmaker's younger sibling, Noah Cyrus, begged people to ''stop being so mean'' to her after she unveiled her drastic new haircut, similar to the half-shaved looks previously sported by Rihanna and Jada Pinkett Smith, on Instagram on Thursday (07.11.13).

She wrote: ''Everyone please stop hating on me. I'm my own person I can do whatever I want. Please stop being so mean. Do you think I enjoy reading comments tell[ing] me I'm ugly and I'm trying to be someone I'm not when I'm only being myself.''

She added: ''I can't believe the words people are saying to me right now. Please I beg of you just stop.''

Miley also sparked controversy when she chopped off her long brunette locks in August 2012 in favour of a blonde pixie cut.

She initially vowed never to grow her hair long again, but the 20-year-old 'Wrecking Ball' singer admitted earlier this year that she was taking hair-growth vitamin supplements.

Miley recently revealed that she is incredibly protective of young Noah and even monitors her social media usage.

The singer said: ''She says, 'I'm talking to my friend', and I'm like, 'Are you sure that's even your friend?' There are so many fake Twitter accounts. I was following a fake of my mum for two months.''

Noah also hit the headlines late last month after she was allegedly spotted driving a Fiat 500 vehicle ''around town'' with her father, Billy Ray Cyrus, in the passenger's seat.

The pair were spotted in Toluca Lake, California, but state law deems that young drivers are required to be 15-and-a-half years of age to hold a learner's permit.