O’Brien flew to Perth on Tuesday night after learning his stepfather, Ralph, had died.
The Magpies have granted the defender indefinite leave and Collingwood football manager Geoff Walsh confirmed it was unlikely the youngster would play in the decider of the pre-season competition.
“I’ve spoken briefly to him this morning but I couldn’t say when he’d be back, other than it’s obviously very unlikely that he’ll take his place on Friday evening,” Walsh said.
Asked whether O’Brien could miss his team’s opening clash of the home-and-away season, Walsh said the club hadn’t thought beyond the next couple of days.
The 22-year-old, who missed Collingwood’s NAB Cup semi-final win against Essendon, is likely to be given as long as he needs to overcome the personal tragedy.
O’Brien met his biological father when he was 19 but called his stepfather “dad”.
