That day Everest returned from her trip and found Sunny very sad.

She wasn't the type of puppy to be capricious but when she set her mind to something she was determined to accomplish it unless Pearl or Everest forbade it...

Yes Pearl was her "older brother", Everest was something like her "mother", she obeyed and respected the decisions that these two made. Sunny wanted with all her might to go on her expedition but she knew that Pearl must have had a good reason for forbidding her, in the end the day was over and now it was time to sleep.