The christening of Prince William and Kate Middleton's baby Charlotte was indeed a big event as attested by the presence of more than 3,500 well-wishers. While the actual ceremony at the St. Mary Magdalene Church remained private, people were encouraged to wait outside to have a glimpse of Prince George's little sister. However, Pippa Middleton also received a lot of attention that day for wearing an outfit that's nearly identical to her sister's.

The two sisters opted to don cream-colored ensembles for Princess Charlotte's christening. It isn't the first time that Pippa Middleton has been accused of imitating her older sister's outfit. 

As reported by Life & Style, at Prince William and Kate Middleton's wedding in 2011, Pippa Middleton chose to wear a dress which closely resembled her sister's bridal gown.

Etiquette expert William Hanson believes that Pippa Middleton should try to wear something different from her sibling's outfit.

 "Had it not come up in conversation on the telephone as to what each of them would be wearing? Yesterday's minor fashion incident is just plain irritating: Pippa doesn't need to resort to cheap tricks. She is perfectly pretty in her own right and the press would more-or-less have gushed over whatever she wore," he told the Daily Mail.

Despite such observation, the Palace kept its focus on the Prince William and Kate Middleton's baby Charlotte.

"Thank you to everyone who joined us in celebrating Princess Charlotte's christening yesterday - such a happy day! And a big thank you to the thousands who came along to Sandringham to make it such a lovely moment for the family," read the Kensington Palace's official tweet that day.

Us Magazine reported that following Princess Charlotte's christening, her grandmother Carole Middleton is staying with the royal couple to assist in taking care of the newborn.

The royal duo reportedly did not hire additional nannies although they have enlisted the help of a night maternity nurse for a couple of months.