You're welcome.
Query "TTS voices" in Google Play and you should get a bunch of apps regarding voices and TTS programs. There should be a control in his tablet's Settings function that will let you choose which voice program to use if you install another one.
Cool Reader allows you to install a choice of dictionaries. I am using ColorDict:
https://play.google.com/store/apps/d...=search_result
It also allows the installation of sub-dictionary programs - thesaurus, spelling, irregular words, Spanish/English, German/English, Chinese/English, Japanese/English, various Bible dictionaries, etc.