Fablehaven
A book series that's full of magic and stupid siblings. It's about a brother and sister who both either get the good magic or the bad magic, but they still have to work together. The sequel series is called Dragonwatch.
'My sister got the good magic, and I got the bad. It's not fair.'
'I can't believe we still have to team up even though we're on opposite sides.'
'This book is like a never-ending argument between two annoying siblings.'