Kate and Rio Ferdinand announce 'hugely important' BBC documentary on becoming step-family

Kate and Rio Ferdinand and their family are the focus of a new BBC documentary. (PA)

Newlyweds Kate and Rio Ferdinand are set to be the focus of an upcoming BBC documentary delving into the trials and tribulations of becoming a step-family.

Kate is stepmother to Rio's three children, Lorenz, 13, Tate, 11, and eight-year-old Tia whose mother Rebecca Ellison died in 2015 aged 34 from breast cancer. Rio and Kate: Becoming A Step Family will explore the former TOWIE star’s integration into the family.

It comes after Rio fronted another documentary for the broadcaster, Being Mum and Dad, which explored his struggles as a single parent after his first wife's death and how he and his children navigated their grief in the wake of her passing.

Read more: Kate Ferdinand reveals concern over trolls who target her relationship with husband Rio's children

The couple said of the new show: "The positive response to Being Mum And Dad in 2017 and the way it helped others going through a similar situation was overwhelming.

"For that reason we were both compelled to tell the next chapter in our lives together.

"We hope Becoming A Step Family will give a unique insight into step-families and the journey through grief, whilst also providing an intimate look at our lives together."

The pair also shared the news to their Instagram followers, with Kate writing: This is a hugely important and personal project for @rioferdy5 and I. For the last year we have been filming a new @bbcone documentary ‘Rio and Kate: Becoming a Step Family

“We have been on such a journey and we really hope the film will help other step families and those experiencing the journey of grief.”

Kate and Rio wed last September with his three children all taking part in the ceremony.

Former reality star Kate recently revealed there could be plans to expand the family in the future, and that her step-children had asked about their baby plans at the wedding.