Jamie (The Empty Child)
In January 1941, Jamie was killed and had a massive head trauma on the left side, partial collapse of his chest cavity on the right and a gash on the back of his right hand. He was reanimated by the Chula nanogenes that had leaked out of a crashed medical transport ship. His only thought was to be reunited with his mother, and he wandered the streets of London, a gas mask forever merged to his face, asking everyone, "Are you my mummy?" Because the nanogenes were unaware of what a human looked like, they began transforming all humans with whom they came into contact into gas mask zombies.
Whilst aboard the Orient Express, the Twelfth Doctor briefly asked the Foretold the same question in an attempt to bring humour to his possible last few seconds of life. (TV: Mummy on the Orient Express)