Why Is It Called...?

We were on vacation a couple weeks ago and decided to try to do a couple of days at Disney before our passes expired. We were forced to change this to one day as our passes were blacked out for Good Friday. It's just as well as the place was obscenely crowded. As I was explaining all this to the kids, Maya asked what Good Friday was. So, I decided to explain it the best my Jewish upbringing would allow. "Christians believe that Good Friday represents the day that Jesus was crucified. Easter Sunday is the day he rose from the dead." She thought about that for a moment. "That's the day he was crucified?", she asked. "That's what the believe," I answered. "Then why do they call it GOOD Friday?" "That's a very good question," was all I could come back with. Anyone?