Easy riddle

this is very apparent, and i woul;d say you are very stupidnot ot get it.. jk
well. Mrs. Corby woke up on Sunday morning to see that her husband was dead. She immediately called the police and the following were the suspects.
The maid-said she was getting the mail
The butcher-said he was working in the kitchen
The wife-said she jyst woke up
The nurse-said she was taking care of the children

so... who was the murederor and why?

The maid. Because there is no postal services to private dwellings on the Sabbath.....😏