His father Terry, like Sean a centre, was an All Blacks star before being cut down in his prime by a serious shoulder injury. He became a fervent Scottish supporter when his son started playing for Scotland and won 29 caps during one of the nation's most successful periods.
Sean admitted his father would have split loyalties on Saturday but that he would be delighted to see Scotland pull off a shock victory. Sean told The Scotsman: "This will be the first time I've coached against New Zealand but I don't see this as a game against my home country - it's simply a match against the best team in the world.
"But all the pressure is on them. I have spoken to my old man and he has enjoyed watching them, and how they are playing, which is fantastic, but England have shown they are not invincible - that they have a soft underbelly.
"My dad would be delighted if we did it, because that would have meant a great game of rugby. But he can't lose. He has two teams - the All Blacks and Scotland - but being involved with a team that beat the All Blacks would be my biggest achievement, certainly as a coach, so he'd be delighted for me."
Sean insists that once all 15 players master the style of play wanted by Frank Hadden, they will be capable of better performances. That will please the expected 45,000 crowd - the biggest autumn Test attendance since 2002, when South Africa were stung by a courageous Scottish display.