Even though we still think of them as children, under the law when a teen turns 18, they are considered an adult. Being an adult allows them to vote, serve in the military, serve on a jury, sign a contract and get married without your consent. This is a big change from when they were 17.

Yes, we all know the rules about paying off a mortgage: if she had a low interest rate mortgage she could take the extra cash and earn more in the market. At the time she still received a tax break for having mortgage interest. She wouldn’t want to be house rich and cash poor, and a mortgage is a hedge against inflation.