We now know that speaking more than one language has many benefits that can include better brain engagement, stronger executive functioning skills, and delayed onset (by as much as five years) of dementia and Alzheimers.
https://www.kqed.org/mindshift/46188/why-multilingual-people-have-healthier-more-engaged-brains?fbclid=IwAR0f0RnCobnS1paMi0EqBZIA5obkrkXxn0meS1DkNicMp6iuGPyauhdarOA