Members of the British royal family arriving at Prince Louis' christening.
On Monday, Kate Middleton wore a simple Alexander McQueen dress to Prince Louis' christening at St. James' Palace in London, UK.
The Duchess of Cambridge accessorized the dress with a Jane Taylor headband adorned with flowers and lace.
Middleton has worn neutral-colored Alexander McQueen dresses with floral headpieces at the christenings of all three of her children.
All three of her outfits have complemented theroyal christening robe worn by royal babies since 2008.
Kate Middleton looked radiant in a simple off-white dress at the christening of Prince Louis at St. James' Palace in London, UK, on Monday.
According to People, Middleton wore a dress designed by British luxury fashion house Alexander McQueen. The simple number featured structured ruffles at the shoulders and a sleek V-neck. The Duchess of Cambridge finished the clean, romantic look with a matching off-white Jane Taylor headpiece adorned with flowers and lace.
Kate Middleton wore an Alexander McQueen dress to Prince Louis' christening.
Alexander McQueen has proven to be one of Middleton's favorite brands over the years. The fashion house designed her iconic wedding gown in 2011, in addition to the duchess' dresses for the christenings of her first two children.
In 2013, Middleton wore a pale yellow dress with dramatic ruffle detailing to Prince George's christening. She accessorized the pastel number with a matching yellow fascinator, decorated with an oversized flower and lace.
Middleton at Prince George's christening in 2013.
Two years later, in 2015, Middleton opted for a white collared blazer dress when she attended the christening for Princess Charlotte. On her head, the duchess wore a white fascinator featuring a cluster of white flowers.
Middleton at Prince Charlotte's christening in 2015.
In addition to floral headpieces and Alexander McQueen dresses, Middleton's christening outfits also share another common thread. At each service, the duchess has donned neutral colors that complement the official royal christening robe, which is made of Spitalfields silk and Honiton lace.
According to the Royal Collection Trust, which manages the Royal Collection, the robe is an exact replica of the original christening gown, which was commissioned by Queen Victoria for her eldest daughter, Princess Victoria, in 1841. Prince Louis is the eighth royal baby to wear the replica since it was first used at the christening of James, Viscount Severn, in 2008, according to the Daily Mail.
Prince Louis' christening will feature a few other traditions, according to the royal family's official website. The young royal will be baptized by water from the River Jordan, held in the Lily Font, which has been used in every royal christening since 1841.
Following the service, Prince William and Kate Middleton will serve a tier of their wedding cake from 2011— as commonly done by members of the British royal family and non-royal couples in the UK.