Final answer:
The 'blood child' apparition in the passage represents betrayal, symbolizing the loss of lives and the betrayal of trust.
Step-by-step explanation:
The 'blood child' apparition in the given passage represents Betrayal. The apparition appears to symbolize the betrayal of the soldiers' companions who have lost their lives, as described when the child looks at the motionless figures with wonder. The child's understanding cannot accept this phenomenon, suggesting that the apparition represents a betrayal of trust and the ultimate sacrifice made by those who lost their lives.