The name wasn't a giveaway, so here it is - they're father and son.
If you've been watching and enjoying - no, that's not the right word - experiencing... ?... 'Chernobyl', you'll no doubt have been blown away by the performances from the entire cast.
Leading the pack, however, has got to be Jared Harris. Having starred in the likes of 'Mad Men', the hugely under-appreciated 'The Terror', and Guy Ritchie's 'Sherlock Holmes: A Game of Shadows', Harris has been doing what the best actors do - plugging away and building an incredible body of work, all while minding his own business.
Yet, given how 'Chernobyl' has captured people's attentions, a lot more people than you'd expect are only now realising that Jared Harris is the son of esteemed Irish actor Richard Harris. Jared Harris, however, was not born in Limerick like his father. In a recent interview with Independent.ie, he explained the situation. "I was born in England, I was raised in England, but a part of me will always be Irish," said Harris.
"This might sound strange to some people in Ireland, but I support the English football team when they are playing in the World Cup and then I support the Irish rugby team when they are in action, so what does that make me?"
Jared Harris was one of three sons his father had with Welsh actress Elizabeth Rees-Williams. His younger brother, Jamie, is also an actor and has appeared in the likes of 'Marvel's Agents of SHIELD' and 'Kingdom' alongside Frank Grillo. His older brother, Damian, is a director and gave Jared his first film role in 'The Rachel Papers' in 1989.
The final episode of 'Chernobyl' airs on Sky Atlantic next Monday.