"She was the purest, most amazing wife, mother and friend to have ever walked this Earth," her husband said in a Facebook post.

"I will never get over this, she was my soulmate, my childhood sweetheart, my one and only. The foundation of my entire family and the strength that held us all together.

"My boys had to witness something nobody should ever have to see of any age, but they know Mum died an absolute hero."

Nathan said he had also set up a fundraising page "for my sons and security after the tragic loss".

In the post on that page he described how his wife, who he had been with for 22 years, had held on to their son until he was rescued "but didn't have the energy to save herself".

He added: "I just have to be thankful for the hero she was in life and in death, and totally grateful for the fact my boys got out safely."