Sirius, the Dog Star — Angeli Perrow

In this story, Nathan, a young Black crew member on a coastal schooner, forms a friendship with a huge Newfoundland dog named Sirius. Newfies are water dogs, strong swimmers famed for their instinctive ability to rescue foundering swimmers and even small boats. When Nathan's schooner is wrecked on ledges near Maine's infamous Boon Island light one dark, windy night, the dog's bravery and loyalty are put to the test. The lifeboat full of exhausted sailors must somehow cross the raging surf to reach the safety of the lighthouse keeper's home, and only Sirius can get them safely through.