The Storm Whale in Winter by Benji Davis

A follow-up to the best-selling The Storm Whale, winner of the 2014 inaugural Oscar's First Book Prize in association with the Evening Standard.
  It’s winter time and Noi’s island is covered in a blanket of snow. Even the sea is icing over. Noi is worried about the little whale he saved last summer: Can he survive the harsh conditions? Little does Noi know that it’s the little whale’s turn to save him. A magical and touching story about a lasting friendship. A truly beautiful work packing a real emotional punch.