A third boy has been named as Darnell Harte, also aged 15.
Louise Thornton, 34, known as the boys' Godmother/Aunty Lou, said there were no words to described the loss of the two "cheeky chappies", Ellis, 12, and Elliott, 15, who were so loving towards their family.
She said: "Elliott was the eldest. He was very loving and very trusting. He was so proud of his family, his mum and dad and his two sisters, Ebony, 16, and Bronte, five.
"Ellis was the youngest and he looked up to Elliott and Ebony as well. They had a little cousin called Caidi who they adored.
"We are just devastated. We can't believe they have both gone as that just doesn't happen.
"We were so proud of the boys. They will be hugely missed by the family. It will leave a huge devastating void. As a family we have already been through so much.
"I'm devastated. They were very well-loved. We just can't describe how much these little boys have left a big void in our family."