We have a single ceiling light in our living room controlled by a single light switch. Since moving into this house we have found that if we try to turn it on it flips the circuit breaker. If we turn it off again and flip the circuit breaker back on the rest of the lights in the circuit work fine. We have not used it since. However, my brother came back and unaware of this issue he switched it on, and flipped the circuit breaker. My wife then flipped the circuit breaker back on whilst the light switch was still on. This seemed to blow the circuit, and now, even with the problem switch turned off, flipping the circuit breaker back on we found only one light on the circuit now works. The others no longer some on.

What might have happened and what might need to be done?

The original light switch was shorted out and needed replaced initially. Now you need to replace the other sockets or switches provided the wiring is not fried. Or the actual circuit breaker is fried. This should have been addressed long ago as it was a potential fire hazard when unfixed.