andrea canning: jasmin caldwell reports on fort hood for nbc affiliate kcen-tv.as about 214,000 acres. there's about 65,000 soldiers roughly. so it's a very, very large place. andrea canning: mayra agonized. the place was so large, her sister could easily be forgotten. and she didn't like what she was hearing when she said she spoke with one of vanessa's staff sergeants. mayra guillen: he just wasn't able to tell me anything. and that just made me even more upset. andrea canning: too upset to sit home and wait. you headed to fort hood? so you needed answers. right. andrea canning: mayra says she was surprised by the reception she got at the gate. what did they tell you? they tried to ask me if i knew anything. i'm like, if i knew anything, i wouldn't be standing here. so this is a mystery, what happened to your sister. no one knows anything? everyone claims that they just didn't know. andrea canning: army investigators did tell the family one terrifying thing. mayra guillen: everything was there-- her car, her keys, credit, debit card, id itself, her military id.