The Fowl Twins by Eoin Colfer

Myles and Beckett are eleven-year-old twins, but the two boys are wildly different. Beckett is blonde, messy and sulks whenever he has to wear clothes. Myles is fanatically neat, he has an IQ of 170, and he wears a fresh suit every day like his older brother, Artemis Fowl.
Perhaps you have heard of the Fowl family and their adventures?
Trigger & Content Warnings:
- Physical injury
- Gun violence
- Kidnapping