Based on observations of parents in the library, my main recommendation to parents would be make sure that support and encouragement doesn't turn into undo pressure. I've seen children desperate to borrow a book in a series they're crazy about, only to told sternly to put it back because it's "too easy," and doesn't stretch them enough. ("He's gifted, you know," they tell me proudly.)

Yes, they're gifted and talented children, but they're still children. They can't be busy achieving all the time. Let them relax with "easy" books, or run round madly, or play games. Keep it fun. Allow them to pursue their enthusiasms, however bizarre or unfashionable these are. My parents obligingly took me to endless castles and let me run round the garden dressed up in historical costume and endured neverending games of Kingmaker, all of which probably did far more to lead to my studying history at Oxford than any amount of pressure to study and achieve.