Dark Deeds at Deathwood by Hazel Townson
Damian Drake has an unexpectedly exciting life for a rich kid in middle school. He has got into the papers again, having been rescued from kidnapping this time. And it inspires Tracey Fallows to write to him. They strike up a correspondence, and although he does check that there are no crazy criminal brothers (as happened before!), he doesn't spot the militantly political mother. His letters are chattily full of visits to his parents from the prime minister and the rest of the Cabinet, which tells the mother more than she needs to know about how to upset the government!