What’d your Dad do when he sprayed the insecticide? Run for cover?
No, he just stood there. The interior wall was between him and the bees. I stood there too... but on the opposite side of the room, near the door. We never saw a bee inside the house. I think the first indication they were in the wall was that I found a few bees in the attic, the stairway to which came into my room (but was behind a door).