PART 2: THE SMELL BETWEEN THE TWINS’ ROOMS LED EMILY TO A CLUE NO SPECIALIST HAD TESTED

When?”

“Last summer. Lake Como.”

Reeves looked uncertain.

“You said the improvement was mild.”

“It was obvious to me.”

“Symptoms fluctuate.”

“Yes.”

I interrupted.

“How long were they away?”

“Three weeks.”

“Did they improve immediately?”

Nathan thought.

“After maybe four days.”

“And worsen after coming home?”

He went still.

“Yes.”

“How fast?”

“Within a week.”

Dr. Reeves no longer looked dismissive.

That mattered.

I asked:

“Any other trips?”

“Florida. Vermont.”

“Better there?”

Nathan thought.

“Florida, yes.”

“Vermont?”

“No.”

“Where did you stay in Vermont?”

“Our lodge.”

“Same ventilation vendor?”

Thomas answered from the doorway.

“Yes.”

The room became very quiet.

Nathan looked at him.

“Same odor system?”

Thomas checked.

“Yes.”

Now we had pattern.

Not proof.

But pattern.

The industrial hygienist arrived that evening.

Dr. Maya Patel.

Calm.

Direct.

She took air samples.

Surface samples.

HVAC condensate.

Dust.

Cartridge residue.

She reviewed maintenance records.

Then asked a question nobody else