Two Sentences That Will Get Kids To Tell The Truth

According to a new book called 'NurtureShock', you only need TWO sentences to get your kids to tell the truth.  When you think they might be lying about doing something, tell them: "I won't be upset with you if you did it, and if you tell the truth, I'll be really happy." You can also use: "I'm about to ask you a question, but before I do that, will you promise to tell the truth?"

My guess is the author did these tactics on kids under six-years-old.  Any kid older than that KNOWS better.  Hell yes you're going to be upset if they destroyed the house or shaved off their sisters hair!  I have teenagers and a seven-year-old, I'm going to try this and see how far I get this week.

Parents what do you think?  Will it work?