For most of his life prior to losing track of his mother, Rose McLoughlin, Kidd wandered the Inisa looking for her and avoiding trouble as best he could while doing so. In the end, he found her with the Fianna Mór and so, decided to stay with them where he spent much time serving as cook and housekeep under the prior Bookkeeper Kiora Adair.
After being kidnapped in the Zmejkrilo mountains, his mother managed to rescue him and he aided her in destroying the ex-mother of Ferelith Adair of the Unseelie Courts. Once they won the race around the country that would determine who would send the first expedition between the Unknown and the Unknown, he returned home with her where he become her understudy in naval warfare for some time.
Eventually, age would catch up to Kiora, and Kidd would take over for her as Bookkeeper of the Fianna Mór. He would reorganize the guild into a semi-anarchic cluster of cells, called Conclaves, that would be self-sufficient in their duties. Thus, Bookkeeper as a title was relegated to a form of over-coordinator rather than leader.
Here, Kidd would come into his own as an adventurer. Traveling to places such as Etomesto and Otherworld. One account claims his arms and armor are archfey-made. Customized to his specifications as a gift from his aunt Ferelith Adair who commissioned it as a reward for aiding her and her nephew during a siege on the Palace of Howling Winds.