It looks like 2018 is going to be a busy, baby-filled year for the Middleton family as Pippa Middleton is reportedly pregnant.

With her older sister Kate due to give birth to her third child any day now, Pippa - who got married to James Matthews last year - is also expecting her first baby, according to The Sun.

The 34-year-old reportedly told friends and family following her 12-week scan, with a source saying: "When Pippa found out she was pregnant, she was obviously thrilled and utterly overjoyed.

"Naturally, big sister Kate and parents, Carole and Michael, were the first people she told — James aside — and they could not have been more delighted. It’s been a tough few weeks for the two families, so this has provided some much-needed happiness and light relief."

It'll also be the second baby in the Matthews family this year, as James' brother Spencer Matthews is expecting his first child with Irish fiancee Vogue Williams - who inadvertently revealed that she was expecting a boy on national television recently.