I was raised bilingual (English and Dutch) because I have lived in the Netherlands for most of my life, but most of my relatives are English (my dad is full English, my mother is half English, half Dutch).
I was born in England and moved to the Netherlands when I was three years of age. We went back to visit family twice a year.
Recently, however, I lived in Wales for almost a year. That helped me to really refresh my English memory.
Not only do I understand the language, I understand both cultures. Small nuances in the way words are understood culturally, can make a big difference for how your text is read and how you come across as a person or company.