Princess Diana's brother shares old family photo with sister without King Charles

Princess Diana's brother Charles Spencer on Thursday shared an old family photo on social media. 

Spencer said that the photo apparently taken in late 80s "shows my sisters and brothers-in-law, flanking my father and stepmother." 

Although Princess Diana is featured in the photo, King Charles is notably absent despite their marriage in 1981. 

Hundreds of guests made up the congregation at St Paul's Cathedral. Charles and Diana selected St Paul's over Westminster Abbey, the traditional site of royal weddings, because St Paul's offered more seating and permitted a longer procession through London.

Sharing the photo on Instagram, Spencer wrote, "Trying to remember what this rather formal family photograph was for - it shows my sisters and brothers-in-law, flanking my father and stepmother, at the base of the main staircase (in the central hallway, known as the Saloon) at Althorp House in the late ‘80s. Perhaps it was something to do with my father’s 65th birthday, in January 1989? Definitely an ‘80s air to it all…. "I'm always intrigued by interior shots from Althorp’s past. Those huge candelabra are no longer on the staircase, and the Saloon’s walls are now white."