Bretton's parents were not particularly talented.
Wiggin was a prime example. He only became an Advanced Level Knight in his forties or fifties, making it nearly impossible for him to advance any further in this lifetime. Advanced Level was his limit.
As for Dianey, while heaven had blessed her with stunning beauty, it had taken away her talent for Cultivation. She was just an ordinary person.
Bretton's exceptional talent for Cultivation seemed more like a case of atavism, as both his paternal and maternal grandfathers had been quite gifted.
That said, talent was only one part of the equation. The more crucial factors behind Bretton becoming an Intermediate Knight at fourteen were his persistent attitude toward Cultivation and Dianey's strict demands and teachings from a young age.
Without these two factors, especially a persevering heart, talent alone would not have been enough.
The world is full of geniuses who ultimately fade into obscurity.
