There is nothing left of Vincent Crabbe for his mother to bury. For a while, she didn't even realize he was dead. For days after the battle she sat waiting for her son to come home. She becomes frantic when he doesn't appear, writing to friends and neighbors and eventually, the Ministry. She decides she will do anything, even call on the blood traitors and misfits that now rule her world, if she could only find her son.
Relief, in a fashion, comes in form of a starched, official looking slip of parchment from the Ministry
According to reliable MOM sources, Vincent Roland Crabbe was killed during the Battle of Hogwarts.
That's all it says. No condolences. No signature. With a few, short words the Ministry writes her son out of the world.
It takes her weeks to accept the truth.