Advantages of a bilingual brain: teaching young children a second language is beneficial in many ways: Tracy Trautner, Michigan State University Extension – January 28, 2019  https://www.canr.msu.edu/news/advantages_of_a_bilingual_brain

“What’s going on inside the brain of a bilingual child?” (KQED) https://www.kqed.org/mindshift/47054/whats-going-on-inside-the-brain-of-a-bilingual-child