Wow, condolences to the family. I ALMOST was crushed by my car!! Story:
I got some insane neon under car lights, curved ones for the wheel wells, long ones for down the sides, etc. Lots of work, so I figured, jack the car up fully so I could get under all of it at the same time. I jacked one corner up a bit, put some bricks under that tire. Jacked another corner up, put bricks under that tire. Once I exceeded the height of the (scissor jack for the spare tire) I put bricks under it, and kept jacking it up. I got it about 3ft off the ground and was satisfied. When I jacked up the final corner I just left it on the scissor jack.
I got under the car, was installing the neon lights, only probably 5 mins after getting it in the air. I kept getting hit in the face with something, I thought it was just rust or dirt falling off the car and hitting me in the face (even though it was a brand new car). A few seconds later I heard a "ting" and got hit in the face again! This time it was a big chunk of something, I looked down, it was black paint. I was puzzled, my car is red, no black paint anywhere? Then I looked over at the scissor jack, it was beginning to fold and the paint was chipping off as it was twisting!!!
I rolled out from under the car just as it folded up the scissor jack and toppled my brick piles and the car came crashing down!!! Just BARELY got out in time

Only damage was to one of the brake lines and some dents and scuffs in the floor from landing on the bricks. Scissor jack was twisted and folded up like a pretzel!
After that I bought a real jack and some nice axle stands

Any time I'm removing a wheel I put the wheel under the car with me, in the event it drops I hope the wheel would stop me from getting crushed.