Owen Farrell expects his mum Colleen to be cheering for a try-less England win against Ireland when he comes up against his dad Andy for the first time.
Only the Irish can prevent Eddie Jones' men from becoming the first team of the Six Nations era to complete successive Grand Slams, one week after the title was retained with a round to spare.
The climax to the Championship places father and son on opposing teams for the first time, Owen as England's playmaking inside centre and Andy as defence coach of Ireland - a role he also performed at Twickenham until his departure after the 2015 World Cup.
It confronts Colleen with a dilemma best solved by the smallest of Red Rose victories at the Aviva Stadium on Saturday.
"We don't really joke about it. It's not like he's playing the game, there's only one of us playing in it and he's obviously got a coaching role," Owen said.
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"I think the only person it will affect is my mum, not us. She just wants everyone to do well. She wants 3-0 England I think!"
Farrell has emerged as the heartbeat of Jones' England - his goalkicking, defence and generalship now matched by a growing artistry with the ball in hand.
How the 25-year-old performs in Dublin will be instrumental to aspirations of seizing the victory that will eclipse New Zealand's world record of 18 successive Test wins.
Farrell combined with George Ford to bewitch Scotland in last Saturday's title-clinching seven-try rout and his father - a former Great Britain rugby league captain - now faces the task of subduing England's twin conductors.
When asked if Andy will have devised a defensive plan to negate his own threat, the younger Farrell replied: "I guess we'll see. Ireland are a good team so I'm sure it'll be a tough challenge.
"We don't speak to each other every day. We speak to each other what I would say is the normal amount, as any family would.
"We chat a bit of rugby, but we also have general chat as families would."
Jones, who is grooming Farrell as the long-term successor to Dylan Hartley as England skipper, is unconcerned by the father-son relationship that spans rival camps.
"They've probably been talking about rugby probably since Owen was big enough to sit at the table," Jones said.
"I think they're both mature enough to get on with it this week. Neither needs any more motivation to do well. They're Farrells - I think that sums it up."
Full-back Mike Brown is among a number of England players to have played alongside the son and under the father.
"They're very similar. They both bring a lot of energy. Owen backs up words with actions. Being a rugby league fan I grew up watching his dad on TV playing for Wigan," Brown said.
"Owen is probably used to this. He's probably not taken a second thought about coming up against his dad because he's so focused on his job in the team."
