If you don't want to accidentally marry your colleague, make sure you watch your phrasing when talking to Siri.
Following a relationship with a contact without using some kind of relative pronoun like "that" or "about" may confuse your voice assistant, as shown in the screenshot here.
Instead of saying "Tell my wife, Erica Sadun is coming for dinner," insert "that." Saying "Tell my wife that" followed by your statement helps separate the relationship from the contact that follows.
Siri does such a good job interpreting speech that sometimes it's hard to remember she's just a bunch of algorithms in a North Carolina data center. Be sensitive to interpretation quirks, and try to avoid them where possible.
