Brooklyn and Bailey McKnight's little sister, Paisley, was at a camp on a smaller arm of the Guadalupe River. The 14-year-old was "just miles" away from Camp Mystic in Central Texas, which has been devastated by the deadly floodwaters spurred by extreme rainfall on July 4.

When tragedies are in the news — natural disasters, plane crashes, fires — parents naturally and unavoidably react by thinking about what might happen to their own children. And children worry in turn about what might happen to them.

We're starting off with analysis of new satellite images that show the extent of the damage caused by deadly flashing flooding in south-west Texas. It has killed more than 100 people including at least 27 at a Christian summer camp.