This is a pretty sad website. I think they are from France so the english on the page is not the best but it's interesting.
It seems like one of the twins drowned the other in the bath and shot herself....
http://www.virtual-memorials.com/main.php?action=view&mem_id=4323&page_no=1 &PHPSESSID=999dbc53d2078542ede6f16d212ac5b9
Frances was dead,she got her father's gun and ended her life,a hole life,and our lives too.I was too shocked,I wanted to call the ambulance,protect my baby,make her come back and give my life if it was necessary...I was scared,and I'm scared now,what will happen to my life without that girls? So I started to scream Bea's name,but she had gone too,probably before Fran.She drowned at the bathtub,and I couldn't do anything for my baby. They were too scary,too cold,I could not recognize in that blood the girls that had changed our lives...