Fiona Bruce uncovered quite the family mystery when she appeared on Who Do You Think You Are? back in 2009.READ: Fiona Bruce on the guilt she faces for being a working motherThe 56-year-old, who is the face of BBC shows Antiques Roadshow and Question Time, discovered that her great-grandfather, Frederick Crouch, died in World War One in mysterious circumstances.The family story is that Frederick failed to duck down when shells began falling nearby, although everyone around him dived for cover.