Rangers midfielder Nicky Law will put family ties to one side in the play-offs as he bids to relegate former club Motherwell, who his younger brother Josh plays for.
The siblings will go head-to-head over two legs next week for a place in the Premiership next season.
After the contest, Nicky will be best man for Josh at his New York wedding.
"I can't be sympathetic and he won't be sympathetic to me either and I wouldn't expect him to be," said the elder Law.
"He's also playing right-back just now and I'm out on the left so it could be me in direct opposition to him," he said of his flat-mate.
"You couldn't really make this scenario up and it's going to be strange. We live together so I might injure him this week or put something in his food - I'll be cooking this week.
"It will be tough for my family but there's nothing you can do. I just need to concentrate on Rangers and Josh on Motherwell.
"I don't think my parents will come. My mum certainly won't. My dad might with my brothers.
"The wedding on 3 June will also be tough because I'm best man... at the minute. One of us is going to be low for the week out in New York and the other will be quietly very pleased."
The 27-year-old spent two years at Fir Park before his move to Ibrox in 2013, while his 25-year-old brother joined the Steelmen from Alfreton Town last summer.
Motherwell are bidding to preserve the top-flight status they have enjoyed since 1987, while Rangers are aiming for a third successive promotion.
"I think we are just running on adrenaline at the minute because it has been a really tough long season," said the Ibrox midfielder after coming through their semi-final against Hibernian.
Rangers lost 1-0 at Easter Road on Saturday, to prevail 2-1 on aggregate.
"The spell in the middle of the season, from losing the manager [Ally McCoist] to probably the new manager [Stuart McCall] coming in was as tough a time for me personally as I've had in my career.
"Mentally, more than anything, it was very difficult. The players' confidence was at an all-time low, no doubt about it.
"The new manager has come in of course and has changed everything around and seems to have got everybody's confidence back. People are playing close to their best again."