The two best interview subjects are children under 10 and people over 70 for the same reason: they say the first thing that comes to their mind. The children don't know what they're saying and the old folks don't care.
Each generation has been an education for us in different ways. The first child-with-bloody-nose was rushed to the emergency room. The fifth child-with-bloody-nose was told to go to the yard immediately and stop bleeding on the carpet.
Children have an unerring instinct for knowing when they are being patronized. They go immediately on the defensive against head-patting adults who treat them like strange beings.