Naming the killer
One night, Mr and Mrs Tan went overseas for some business venture. Unfortunately, there was a murder in a house involving six people - their five children (Alfred, Brenda, Charles, Darius, Eric) and their domestic maid.
One of them was the murderer, another was the helper who aided the murderer in killing the victim, yet another was the mastermind who plotted the plan. Yet another was the mediator who dissuaded the murderer, helper and mastermind. There was also a witness. Here are the facts:
The victim and mediator were of the same sex.
The maid was the only adult among the six.
The oldest person and the helper were not of the same sex.
The mastermind was younger than both the females.
The mediator was younger than the murderer.
The witness was the youngest of the six.
Alfred has only one younger brother, Eric.
Charles is the oldest son.
The helper was older than the murderer.
Who was the murderer?
Of the five children, those with male names are indeed guys while those with female names are indeed girls.