The 22-year-old worked under Ronny Deila last season.
The SPL champions recently took the 22-year-old on trial and will assess his abilities ahead of a potential move.
What could draw the Bhoys to the Everton man is the fact that he spent last season working under Ronny Deila.
Indeed, Junior was loaned from the Toffees to Norwegian side Stromsgodset, where we made 12 appearances.
Celtic currently sit six points clear at the top of the SPL, while Junior has been unable to make an impact at Everton since joining them on a free transfer from Benfica in 2012.
Meanwhile, Celtic travel to Dundee United in the league this Sunday and captain Scott Brown is wary of United's threat, telling reporters:
“I was watching from the stands the last time we played them but it’s probably the best we've played the whole season. Our passing and movement was unbelievable and I think our formation and theirs suited us but they still attacked.
“Dundee United have improved. Jackie and Simon have been working on what they didn’t do against us well and they will perhaps try and defend differently this time."