Formerly of East Malling, Mr Pelly is thought to have asked the princes to be ushers at his wedding to Holiday Inn heiress Lizzy Wilson in 2014.
The six godparents, who also attended with their spouses, are all friends or family of William and Kate.
In 2013, Prince Louis' older brother, Prince George, was also christened by Welby at the Chapel Royal.
The newest addition to the royal family (if you don't count Meghan of course) was christened in the Royal Chapel at St James' Palace.
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Several major firms - including France's Total and Peugeot, and Russia's Lukoil - have said they are preparing to leave. US-Iran relations have been hostile since the 1979 overthrow of the US-backed shah and US embassy hostage crisis.
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The boys were discovered alive nine days after being declared missing, and rescuers are now racing against time to get them out. He said he was also making an "inflatable tube with airlocks", which was "less likely to work, given tricky contours".
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Prince Louis of Cambridge's christening this week was steeped in tradition - from his elaborate gown to the lily font that's been used in the baptism of royal babies for nearly 200 years. Princess Charlotte looked precious in a blue dress and matching headband while Prince George sported a short-sleeved white shirt and navy shorts.
The three-year-old was seen confidently shaking hands with the Archbishop of Canterbury and The Dean of The Chapel Royal, The Right Reverend and Right Honourable the Lord Chartres before heading inside for the ceremony.
Duke and Duchess of Cambridge with Prince George, Princess Charlotte and Prince Louis. Prince William was by Kate's side, supportive as ever.
It is created to look like the robe Queen Victoria's eldest daughter wore in 1841! The royal wore large clustered pearl earrings to finish the look and kept her makeup simple with a smoky eye, rosy cheeks and light berry lips.
Following the 40-minute traditional religious service, guests attended a private tea which included slices of christening cake, from a tier taken from the duke and duchess' wedding cake.
Louis Arthur Charles weighed 8lb 7oz when he was born in the private Lindo Wing of St Mary's Hospital in Paddington, London, on 23 April.