From Posh Spice to world-famous designer, Victoria Beckham is a household name in both the world of music and fashion. And the 42-year-old is also an avid philanthropist, working to support a number of causes that are important to her.

Just a few weeks ago, she flew out to Africa with her eldest son, Brooklyn, to support children with AIDS. Now the mother-of-four has – with a little help from her youngest child, Harper – designed a new t-shirt, which she hopes will raise money for UNAIDS and Born Free Africa.

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Taking to Instagram, Beckham unveiled the new project with her fans – and the simplistic white t-shirt has already proven to be a hit.

Made from soft white cotton jersey, the top features an “exclusive print” of a stick figure in a dress next to a red heart – and, yes, it was drawn by five-year-old Harper herself.

However the child’s drawing includes a nod to the charity; she has ensured that the figure is wearing a red AIDS ribbon, in honour of the occasion.

Read more: Victoria Beckham reveals she kept her first date dress to give to Harper

Proceeds from the shirts, which are available for £90 on Beckham’s website, will go to Born Free Africa, which prevents the spread of the disease from mothers to children.

Beckham, who is a UN ambassador, told Harper’s Bazaar: “For the last few years I have designed an exclusive World Aids Day T-shirt to raise money and awareness on this important day.

“This year, for the first time (and along with a little help from Harper) I've created an adults T-shirt with a matching mini-version for children too. All profits from the sale of these T–shirts will go to Born Free Africa who are doing such wonderful work on the ground.”

Beckham was announced as UN International Goodwill Ambassador in 2014, during the 69th United Nations General Assembly in New York.

“I dream of a generation free from HIV and I know that Victoria’s support will help us to achieve this shared goal,” said Michel Sidibé, Executive Director of UNAIDS. “Her creativity, innovation and outreach will amplify our efforts and bring us one important step closer towards ending the AIDS epidemic.”

Beckham herself added: “This is the beginning of an important journey for me. As a woman and a mother I have a responsibility to support other women. I am proud and honoured to be working with UNAIDS in this new role to help to raise resources and awareness to support and empower women and children affected by HIV.”

Read more: Victoria Beckham opens up about starting out as the "laughing stock" of the fashion world

Meanwhile, if the design on the World AIDS Day Tee looks familiar, it’s because Harper's dad, David Beckham, also used it to design a tattoo on his hand last autumn.

“Apparently Harper is allowed to scribble on daddy,” he wrote at the time.

It seems as if, just like her older brothers, Harper has carved out her own unique talent; she’s been praised by her parents for her art skills, as well as her moves on the football pitch.

Cruz, meanwhile, has debuted his singing talents on social media, and Brooklyn is a keen photographer. And let’s not forget Romeo, who has made a name for himself both as a dancer and as a seasoned fashion model; he took a starring role in Burberry’s Christmas campaign back in 2015.