Okay, so stupid question...

I heard the mother mention an accident but didn't link it to Ray right away. Later, I saw him limping and then no leg... still didn't get it! I really thought I'd seen him walking without a limp before. I guess he was sitting in earlier scenes. I think it was meant to be a shock to realize that he'd lost his leg in that accident... it was for me, and brought much of the anguish in the film together.