With a royal Christening to organise, three children under five and of course, being on maternity leave, it's looking unlikely the Duchess of Cambridge and husband Prince William will attend their favourite event this year.
Prince William and Kate, both 36, have arranged a small, intimate ceremony for their third child, at which only close members of the Royal family will be present.
Harry and Meghan will attend the 40-minute service, as will Kate's pregnant sister Pippa Matthews, and her brother James Middleton.
George was also christened in the Chapel Royal, but Charlotte was baptised at the Church of St Mary Magdalene in Sandringham.
There is speculation that William's outgoing private secretary, Miguel Head, could be chosen to perform the role.
The 16th-century chapel, which is not accessible to the public, is where Louis' four-year-old big brother George was christened in 2013.More news: White House Taps Former Fox News Executive For Senior Communications Job
Ladbrokes says Meghan, the Duchess of Sussex, is unlikely to be asked to guide baby Louis in the Christian faith.
After being worn by 62 royal babies, including Queen Elizabeth II and Prince William, the gown was deemed too fragile to wear, so a replica was created to continue the tradition.
The Queen's first great-grandchild Savannah Phillips weighed 8lb 8oz in 2010, and the newest addition to the Windsors, Zara Tindall's daughter Lena, born last month, weighed 9lb 3oz.
His father said he had "thrice the worry now" when he left hospital with Kate to take the infant home to Kensington Palace.
Pippa's pregnancy circulated when her sister was due to give birth to Prince Louis.
William and Kate had already used Louis as one of Prince George's middle names, but liked it so much they chose to use it again.