Choking on seawater, Janet Cocker and her 7-year-old son used his bright yellow rain jacket to wave down passing fishermen after their boat sank in the Hauraki Gulf on a family fishing trip yesterday.
All seven people on board the 5.8m craft survived bobbing in the furious swells for up to two hours after the boat began taking on water near Ponui Island.
Despite rough weather, the family set off from Kawakawa Bay south-east of Auckland on a fishing trip for Mrs Cocker's 32nd birthday.
After travelling for about 45 minutes they dropped anchor, but soon decided to go home.
"My husband suddenly started screaming to pull up the anchor but it got stuck and the water was coming in. By the time the anchor was up the boat was already sinking."