The Irishman scored at the weekend as his loan entered a third month. Boss Alan Knill hopes Everton will allow the centre-half to stay until the end of the season.
He said: "I'm hopeful we can keep him for the rest of the season because he's a big part of the team.
"He's growing into that leader role.
"We haven't had any indication from Everton whether that's possible, but only because at the moment we're taking it month by month."