Siobhan has been involved with the senior squad since making her debut in a friendly against Holland in Tuitjenhoorn in 2004 after progressing through the Youth ranks. She came off the bench to collect her second cap in the 13-0 drubbing of Hungary a year later.
She improved her prospects by joining Chelsea in the summer of 2007, starting five England internationals in that season.
Now with Bristol Academy, with whom she played in the 2011 FA Women's Cup Final, Siobhan's last England appearance came in the 3-1 defeat of New Zealand in the Cyprus Cup.