I've observed many FAs doing a rather poor job at dealing with passengers who don't speak English. No, yelling the same query louder three times in a row doesn't help.

Some suggestions:
- Explain your mother how the service works and what to expect. Even simple things such as how the meal service works. Ordering is confusing for many passengers who don't understand that they need to order their entrée and salad sauce and that everything else is basically included.
- Give her translations for key words on the menu (chicken, beef, fish, etc.) and drinks (water, etc.)
- Explain to her how to fill in the immigration form as well as the procedure if she needs to connect.
- Tell her to relax. Ultimately, she'll reach her destination and will be fed. Nothing terrible is gonna happen