Pippa Middleton debuts baby bump at Prince Harry's wedding

CHRIS RADBURN/AP

Pippa Middleton and James Matthews arrive for the wedding ceremony of Prince Harry and Meghan Markle at St. George's Chapel in Windsor Castle.

Pippa Middleton is rumoured to be about four months pregnant, and her baby bump is partially visible in photos of her arriving at Prince Harry and Meghan Markle's wedding. 

Middleton, 34, wore a pleated, floral dress. 

In April, The Sun on Sunday reported that an unnamed friend had said Middleton was "thrilled" and "overjoyed" about her pregnancy. 

TOBY MELVILLE/WPA

Pippa Middleton and her husband James Matthews arrive at Prince Harry and Meghan Markle's wedding.

"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," they said.

The baby would be due in October, according to The Sun on Sunday.