iPhone 6 - Dictation mispelled
Make sure that your wife has her own card in your address book. Then open up an email message and start dictating, saying things like:

"Rindy is my wife period."

"Rindy is a person period."

"I am meeting with Rindy today."

"Where is Rindy questionmark"

Each time the computer misspells Rindy's name, go back and correct it. Eventually you will show the computer whose boss, and it will start to spell Rindy's name properly. (Really: there appears to be an algorithm that looks at spelling corrections and uses this as feedback on dictation.)