People have only just realised that Hugh Grant is actually related to one of his Love Actually co-stars.

The actor, 64, portrayed the prime minister in the 2003 Christmas classic but was shocked to find out on set that his grandmother had an unlikely link on of his co-stars.

He discovered that his maternal grandmother was actually the sister of his young co-star Thomas Brodie-Sangster’s maternal great-grandmother.

The teenager played Sam in the movie and his sub-plot was one of the film’s most heart-warming, heeding the advice of his stepfather (Liam Neeson) to tell his school crush how he felt.

On set, Hugh had no idea he was related to actor Thomas until filming had kicked off in a surprising revelation, with fans only just learning of the unlikely connection.

Thomas recently shared: ‘His grandmother and my great-grandmother are sisters… [Hugh] didn’t know. 

People have only just realised that Hugh Grant is actually related to one of his Love Actually co-stars 

While filming the 2003 Christmas classic, he discovered his maternal grandmother was actually the sister of his young co-star Thomas Brodie-Sangster ‘s great-grandmother 

‘I said, “Apparently, you are my uncle or my cousin or something”. Then he kind of remembered my mum and uncle. 

‘So, for the rest of the shoot, he went round saying “Hello cousin”. That felt quite cool.’ 

He told ITV’s Lorraine in November: ‘He referred to me as “little cousin” while filming. He’d come and ruffle my hair.’

Following in Hugh’s acting footsteps, Thomas sH๏τ to minor recognition in Love Actually and became even more well-known as one of the children in 2005’s Nanny McPhee.

Thomas appeared in several films before getting his big opportunity in Love Actually and won the Golden Nymph award at the Monte-Carlo Television Festival for his role in Entrusted. 

He was nominated for a Golden Satellite Award for his portrayal of Sam in the 2003 Christmas movie, earning him more opportunities in the noughties including the chance to play Paul McCartney in Nowhere Boy.

Since then, his career has flourished, voicing Ferb in American comedy Phineas And Ferb and starring in an array of major franchises.

Since his heart-warming Love Actually plotline, his career has flourished, even popping up in Netflix drama The Queen’s Gambit (left: Thomas in November and right, on Love Actually)

He married actress Talulah Riley (pictured, with Thomas in May) last June, in a wedding attended by her ex Elon Musk, and lives with her in a ‘hippy countryside homestead’

Thomas put in a popular display as Jojen Reed in critically-acclaimed HBO drama Game Of Thrones before starring as Newt in the Maze Runner trilogy. 

He has become a darling of streaming site Netflix, playing Whitney Winn in western miniseries Godless in 2017.

He also married actress Talulah Riley last June, in a wedding attended by her ex Elon Musk.

The couple live with her in a ‘hippy countryside homestead’ with four other adults and more than 100 animals.