Oops. Bad Libarian, no big cookie! It would seem that Max and I started the second Spiderwick series (Beyond the Spiderwick chronicles) before reading the first. Color me ashamed. So, we've corrected this, bought some of the earlier ones and even listened to all of the first series on a car trip to NY. For anyone who is interested the series is:
1. The Field Guide, 2. The Seeing Stone, 3. Lucinda's Secret, 4. The Ironwood Tree, 5. The Wrath of Mulgrath
The audiobooks are read by Mark Hamill of Star Wars fame. Very enjoyable!