In a statement Adnan and Arsalaan Habib's family described the brothers as their "family's precious jewels, spreading joy wherever they went".
The statement added: "They were happy and joyous boys who were a central part of the family, always smiling and bringing smiles to everyone they met."
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18-year-old shop worker Christian Trouesdale carried the elderly man's shopping home from an Aldi supermarket in Horwich.
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