Duchess Catherine and Prince Louis (c) Matt Porteous

The Duke and Duchess of Cambridge have released an additional photograph of their two-month-old son Prince Louis, after dropping an initial four pictures.

The royal couple - who also have kids Prince George, four, and three-year-old daughter Princess Charlotte - have dropped another adorable image of their two-month-old son, pictured with a beaming smile while being held by his mother, following the youngster's christening. 

The photo - captured by Matt Porteous - was released on the official Kensington Palace Twitter account, and the caption reads: "The Duke and Duchess of Cambridge have released an additional photograph taken following the christening of Prince Louis.

"The Duke and Duchess hope that everyone enjoys this lovely photograph of Prince Louis as much as they do. (sic)"

William, 36, and 36-year-old Catherine's latest snap comes after they released four official photographs, taken by photographer Matt Holyoak, on Sunday evening.