Hello, 
Thanks for your query.
Some ways to help minimise 
sleep talking episodes:
Get enough rest
Develop relaxing pre-sleep habits such as having a warm bath or a light bedtime snack, drinking warm milk, listening to soft music or reading for 10 minutes.
Go to bed, only when you feel sleepy.
Avoid consuming caffeine and alcohol, watching TV, 
smoking, and having heavy meals at bedtime.
Make sure the bedroom is quiet, cosy, and conducive to sleep. Keep noise to a minimum while you are trying to sleep.
Reduce day-to-day 
stress levels by exercising, stretching or practising yoga on a regular basis.
Keep a regular schedule for meals, medications, chores, and other activities.
Include food that contains 
tryptophan in your diet like 
wheat germ, cottage cheese, milk, eggs, and almonds. Tryptophan increases the level of serotonin [sleep hormone] in your body, and promotes sleep.
I do hope that you have found something helpful and I will be glad to answer any further query.
Take care