The mood of the story is hopeful, and the setting of the burned up house helps create the hopeful vibe in the story. Because, even though their house was burned up, it sets a mood that they can start over, and have a better life.
The setting differs throughout the story, and different setting affect the characters differently, the main setting, which is their grandmother's house I think has a heavy impact on them. The grandmother and the mom don't get along, and that setting for the children must be awkward and nerve-racking.
The character, evolves by becoming very strong and hopeful. At the beginning she keeps a positive outlook on things, and that ends up paying off. When she finds the egg she is very excited, and hopeful for the future. A couple of days after they arrive at their grandmas house, her father arrives, and I think she evolved into a very thankful person.
In the exposition, the conflict is that their house got burned in a fire, and they lost everything they had.
The resolution addresses the conflict by using a connection to the beginning conflict, it wraps it up with a solved conflict, it says, "There's dead, and there's not dead. Sometimes it's better to rise up out of the ashes, singing."
The change in events that were the most influential was when their house was scorched by the fire, and others. I think this because the fire made them start everything from scratch. Another one would be when she grabbed the egg from the nest, because that is what led to many events in the story.