Prince William, Kate Middleton mark Valentine's Day with sweet message

Prince William and Princess Kate celebrated the day of love, Valentine's Day, by releasing a sweet note. 

Taking to Instagram, the Prince and Princess of Wales shared their adorable photo clicked from Catherine's emotional cancer update video. 

The future King was seen placing a sweet kiss on his wife's cheek, whereas, Princess Kate was beaming with joy in the photo. 

The royal couple did not write any text message, instead, William and Kate dropped a red heart emoji with their picture, leaving fans in awe. 

One fan wrote in the comments section, "Happy Valentine's Day to the most beautiful couple in the world."

"Happy Valentine's Day to you both and many more to come," another chimed in.