You shut the door because you are afraid that the zombies will get in after them.
You cruelly watch them swallowed by the zombies.
Fortunately he zombies don't have intelligence so they can't open the door but the Tracy and Shawn are bitten to deadth because of YOU.
You are frighten, guilty, but you are safe for now.
There is no food in the carriage, and your daughter is missing.
"What should I do....."
Hundreds of zombies blocked the door. There is no way out.
You hide in the carriage and wait for the zombie to go away.
You are tired and exhausted.