Louis, who appears to have inherited the brown Middleton eyes from Kate's side of the family, was pictured with his wider family, including the Duke and Duchess of Sussex and the Prince of Wales and the Duchess of Cornwall in photos released to mark Charles's 70th birthday in November.
"The photographs were taken earlier this month by The Duchess at their home in Norfolk", it added.
In two of the photos, a beaming Prince Louis wears a maroon knit sweater and navy blue pants, while in the third photo he sports a blue top with an image of a dog.
With a lifetime of royal duty ahead of him, Prince Louis will soon become accustomed to dressing in his best for formal photographs.
On May 2, Princess Charlotte will celebrate her 4th birthday.
Louis was born on April 23, 2018, becoming fifth in line to the throne behind his older siblings Prince George and Princess Charlotte, ages 5 and 3.
Prince Louis poses in a dog sweater.
People reports that the royal brothers "did not speak to each other" at St. George's Chapel in Windsor Castle while attending an Easter Sunday church service on April 21.
Adding fuel to the fire is news of a plan to send Harry and a heavily pregnant Meghan Markle, who was not present at the Easter service, on an global job that could see them move overseas following the birth of their child. "Wishing him an fantastic Happy 1st Birthday".
The Sunday Times in London reports the Duke and Duchess of Sussex could move to Africa.
Louis' cheerful demeanor in the images is typical of the little royal, according to a source close to the family. They continued, "She has sometimes anxious about being so far away but she is absolutely going to be there for her at the birth".