Complex sentence: The Mitchell Brothers are a rap group from London, England, consisting of cousins Tony Nyanin (a.k.a. Tony Mitchell) and Teddy Hanson (Teddy Mitchell).
Split into simpler sentences: The Mitchell Brothers are a rap group from London, England. The members are cousins Tony Nyanin (a.k.a. Tony Mitchell) and Teddy Hanson (Teddy Mitchell).