Complex sentence: Prior to moving onto Brookside Close, the Grant family were from a run-down inner-city council estate, however through Bobby and Sheila's thrift and hard work had managed to move to the' middle class' Brookside Close.
Split into simpler sentences: Prior to moving onto Brookside Close, the Grant family were from a run-down, inner-city council estate. However through Bobby and Sheila's thrift and hard work, they managed to move to the "middle-class" Brookside Close.