I figure if they can help shed some free insight into difficult child 2 (and indirectly husband), so much the better for our lives. And it may entail some kind of financial incentive, like the ADHD genetic study we joined several years ago, which is a bonus. The principal investigator emailed me yesterday to explain: "Our study is focusing on the similarities and differences between pediatric bipolar disorder and ADHD. As you know, they can appear very similar in childhood, yet the treatments differ radically. We are hoping to learn more about how the brain functions in these two disorders in order to devise a way in which to discriminate them better." I'm waiting for a call from them for some additional questions they have to determine if difficult child 2 is eligible. I'll let you know what I find out!