Just read on another messageboard that the producers are trying to get Susan back (who played Michelle Fowler) to possibly film the final scenes of Wendy Richards character Pauline (Michelle's mum).
I hope this is true, because she's missed her dads funeral and to miss her mums final storyline would be just tragic. And surely Susan would want to tie up any lose ends with her character. Funny that she has never met her younger brother on screen though. So it'd be nice to see her bond with Martin if she ever did decide to come back - even if it was for a brief moment.