Once the presents have been unwrapped and the Christmas dinner has been devoured, family conflicts and blazing rows will hit peak levels on Bank Holiday Monday at 2.59pm, according to a new survey.
This will be when many people will be travelling back from visiting relatives for the festive season and perhaps also preparing to return to work the following day.
It has been dubbed Moody Monday by Kwik Fit who commissioned the poll of 2,000 Britons.
The car journey home from visiting relatives was where 42 per cent of people felt that the season of goodwill would come to a sharp halt.
Criticisms of relatives topped the wide-ranging gripes which would fuel seasonal family rows.
A total of 18 per cent of people said this would tip them over the edge, while 15 per cent were annoyed by inappropriate behaviour and 14 per cent were likely to row over people not helping out around the house.
Mess and clutter would trigger a row, according to 12 per cent of Britons, while the same percentage said that being given bad directions when travelling would cause trouble.
If that was not bad enough 38 per cent said their minds would be turning to worries about over-indulgence and the year ahead.
Financial worries topped the Moody Monday woes for 29 per cent of Britons, 28 per cent said it would be bulging waistlines while 14 per cent pointed towards a post-Christmas anticlimax as a worry.
Some people felt the festive cheer might not have worked for them and returning to work would be a worry for 13 per cent of people while 12 per cent said they might not have properly relaxed over Christmas.
Given that these squabbles can be distracting for drivers, Paul Boulton, of Kwik Fit, urged motorists to be prepared and have a safety check before hitting the road.
He said: “Christmas is of course the most wonderful time of year, but it comes as no surprise that tempers can on occasion boil over in the car on the way back from several intense days of living at close quarters with family.”