The group - who were rocked by the shock death of their 33-year-old bandmate last October - are considering going on the road again but admit they will feel strange going on stage as a four-piece.
Singer Mikey Graham said: "Maybe a hologram would be a fitting way to do it because then it'd be like he's on tour there with us."
The group are preparing for the release of their new album 'Brother' - which features vocals by Stephen - and although they would love to tour with the record, are unsure of whether their grief can withstand it and are already looking into different ways to help ease their pain.
Ronan Keating - who is also joined in the band by Keith Duffy and Shane Lynch - added in an interview with the Daily Star newspaper: "If the record goes well we'd love to tour at the end of the year, but we don't know right now if we can face it. We've overcome other obstacles, so let's see what happens.
"'Love Me For A Reason' and 'No Matter What' are going to be tough without Stephen but maybe we could do a different version so it doesn't break our hearts every time we try."