William II is portrayed as dying in bed after an accident, with his wife Anna Paulowna being present. In truth, he suffered from health problems and dyspnea; the king died in his chair, being put there by his doctor after panicking due to his illness. Anna Paulowna wasn't present because the doctor feared the emotion would worsen the king's health.
Prince Maurice of the Netherlands didn't die from pneumonia, but from meningitis.