While the Paisley side have failed to win a game so far, they are at least spared sitting bottom of the Scottish Premiership by the 15-point punishment handed to Saturday's opponents Hearts for calling in administrators.
But the elder McGinn - now playing for Sheffield United after moving north from Watford in the summer - has even more to worry about with the Blades currently propping up the rest of the Sky Bet League One.
Only middle brother Paul, 22, is doing anything to protect the McGinn family name with his Dumbarton side enjoying a decent start to their Championship season.
It has been a bad enough couple of months for the other two, but 18-year-old Saints midfielder John admits their dad Stephen Sr is the one really down in the dumps.
"It's hard for Stephen and I but it's my dad who is suffering more than anyone," said the Scotland Under-21 cap. "He really takes our results to heart. At least Paul is doing well with Dumbarton.
"Iain Murray really seems to trust him and he's at least doing his bit for the family."
Despite starting the season 15 points ahead of the Jambos, Saints face the prospect of seeing their lead over the Gorgie men being slashed to a mere six should they lose in Edinburgh on Saturday.
But relegation battles have become an all too familiar occurrence for St Mirren since they returned to the top flight in 2006 and the youngest of the three brothers can at least turn to Stephen, 24 - a former Saint himself - for advice on how to cope with life at the bottom.
John McGinn, who won a recall for Monday's 1-1 draw with Aberdeen after losing his place in Danny Lennon's team for the defeats to Partick, Motherwell and Hibernian, said: "Stephen spoke to me when I wasn't playing. He had a really bad injury when he was at Watford and told me to be thankful that I was still fit and healthy and to go and get myself back in the team.
"So I was even more determined to do well on Monday night when I got back in. It made me even more motivated to keep my place because I realise how lucky I am.
"Stephen was involved in a couple of relegation battles at St Mirren, two years running actually. But he didn't expect to be involved in the same thing at Sheffield United.
"There's a lot of pressure on their boss Davie Weir but, just like us up here, he's hoping to help the team through and make it easier for the manager.
"We've spoke about what it is like playing in these situations and his advice to me was just to play without pressure. If you let everything get on top of you, you won't play to your best ability."
Gary Lock's men have picked up two wins and a couple of draws from their opening eight league games to put the pressure on St Mirren. But John McGinn insists he would still rather start the game in Lennon's camp.
"Every game is a cup final for us now," he said. "We are down there and need to get ourselves out this hole we have got ourselves into.
"But I still definitely prefer to be in our position than theirs because we are higher up in the table.
"It's not nice because I've got a lot of friends at Hearts from my time with the Scotland set-up. It's not nice to see them going through administration and people losing their jobs.
"But the team have done really well. Now we just need to hope we can get the better of them."