Just awful. I grieve for the family and I could not imagine the horror of losing a child so young. And I guess people grieve in their own way. They look for maybe, their traditions, on how to grieve.
I can only go by what the bible says, as you have laid out. Grieving and praying to anyone that is dead, is not biblical. It's a Roman Catholic practice rooted in paganism.
And sadly, i think many in that faith, feel that they can make 'saints' out of their friends and family that have passed away. Which just isn't biblical. But alas, that church has always held the traditions of men higher than what Scripture actually reads.
Just an awful situation. Urgh.