Kate Middleton talks about royal baby number four and gives update on little Louis

The Duchess of Cambridge spoke about the possibility of another royal baby.

Kate has previously spoken about being "broody" but during a visit to Bradford the royal mum revealed the Cambridge clan isn't likely to expand any further.

"I don't think William wants any more," the 38-year-old said when asked about the possibility of baby number four.

Kate had the candid chat with 25-year-old fan Josh Macpalce, who is autistic and has DiGeorge syndrome, reports Hello! magazine.

But it seems the mother-of-three has her hands full, with their youngest Prince Louis growing up fast.

During a stop later in the day at Khidmat Centres, the Duchess revealed the toddler's latest milestone while chatting to locals at the Older Yet Wiser workshop .

The proud mum revealed their 19-month-old son is "balancing".

"Kate said Louis had started to tell her 'Mummy, I'm balancing' and she said it was really nice to see him turning into a little boy from being a baby," Jo Broadbent, a grandmother who is a full-time carer for her six-year-old granddaughter told the publication.

"She's obviously very proud of her children," Broadbent added.

Prince Louis was last seen in public just days before Christmas when he arrived with his mum and sister to Buckingham Palace for the Queen's Christmas luncheon.

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The toddler, who turns two in April, didn't join the rest of the family on the walk to church in Sandringham on Christmas morning.

However his big brother and sister, Prince George and Princess Charlotte made their debut this year, walking alongside their parents and proud granddad, Prince Charles.