It's a good time to listen to your children's speech. Remember to encourage them to talk and to focus on their content (message). Let them know 4-5 positive things to one fix it.
If they need more help than one fix it, You may want to consult your local professional speech language pathologist (SLP.) They are good at fixing all sorts of speech and language issues.
HERE ARE SEVERAL PLACES TO CHECK FOR SLP PROVIDERS
1. ASHA.org http://www.asha.org/
2. State occupational and professional Providers: https://secure.utah.gov/llv/search/search.html
3. insurance company listings. (I won't be on that list, as I'm not an insurance provider). Many good providers are not insurance providers.
4. Your local school district may have a list of private providers,
5. Your local Universities may have a list of private providers.