Thanks, Kaona!
Hmm… from what I remember of high school psychology, people who grow up bilingual use their brains differently than people who are monolingual. So maybe there are differences in how I learn Japanese versus someone who is learning a new language for the first time, but I don’t notice them. One conscious advantage, I think, is that since I already know Traditional Chinese, it makes learning Kanji seem much less daunting. Although, learning new pronunciations/readings for them does get confusing at times!