Oh, my dear, I know I speak with many others in saying I'm so, so sorry. What a terrible thing to happen, and I hope your family will be able to come together to support each other, especially your cousins, in your grief and loss. Terrible things happen, and we can't always know why. Sometimes knowing why doesn't help much. Please feel cared about, even though you don't know many of us who are sad for you. Thank you for your generosity in sharing information about what happened. It can't have been easy for you.
Of course, no need to reply.

Karen