What happened to the two kids from Westingtown who went into the Westing house?

After entering the house, the two boys immediately turned and ran the other way, acting like they were being chased by a ghost. One of the boys ran off a nearby cliff, the other has been a mute ever since..... say nothing more than the same two words, over and over again.

“One fella ran out crazy-like, screaming his head off. He never stopped screaming ’til he hit the rocks at the bottom of the cliff. The other fella hasn’t said but two words since. Something about purple.”

“Yep, that poor fella just sits in the state asylum saying, ‘Purple waves, purple waves’ over and over again, and his scared eyes keep staring at his hands. You see, when he came running out of the Westing house, his hands was dripping with warm, red blood.”