Death in the Home...Does it have to be Disclosed?

So, lets say I represent the buyer...

My buyer purchased a home without knowing that someone died in one of the bedrooms. Should this have been disclosed to my buyer...even if the contract states that "no disclosures to be provided by seller." After finding out about this, the agents gives me a Biohazard cleanup report from a certified company stating that everything has been cleaned up.

-Should this have been disclosed before the purchase?

-Is the listing agent responsible for getting me the biohazard cleanup report before the closing?

Please let me know what your experience tells you...

Thank You