What does 'had been' mean? To me 'he had been' seems unnecessary if 'in' means 'over the last'.
He could not help feeling that his first foray into Occlumency had weakened his mind’s resistance rather than strengthening it, and he wondered, with a feeling of great trepidation, what had happened to make Lord Voldemort the happiest he had beenin fourteen years.
Top answer
It's fine. It's a backshifted reporting of "I wonder why Lord Voldermort is the happiest has been for/in the last 14 years".
— Fivejedjon
It's fine.
It's a backshifted reporting of "I wonder why Lord Voldermort is the happiest has been for/in the last 14 years".
Free · every Monday
Get the Weekly English Kit 📬
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.