General Aviation News will often reprint excerpts from US National Transportation Safety Board (NTSB) accident reports, including one that involved a Cessna 206 in Stanwood (Washington) where there was one fatality. In the incident, a 55 year old pilot with multiple ratings and 4,200 hours (including 474 hours in seaplanes), was coming in for a landing in an aircraft mounted on amphibious floats with his son as a passenger. The aircraft was part of a flight of three floatplanes coming in to land at a lake the pilot had never landed at before and his intention was to land in between the wakes made by the other aircraft.
However and upon approaching the lake, the pilot got into a discussion with his son and he likely forgot to retract the landing gear in order to make a water landing. When the aircraft made a touchdown, its nose dipped and when the pilot went to retract the flaps and apply back pressure, the aircraft nosed over and filled with water.
After the accident, the pilot could not recall raising the landing gear nor verifying its position nor hearing an audible landing gear position-warning alert. The pilot also reported that 12 days prior to the accident, he had suffered a loss of a close family member and it was only after the accident that he realized he was suffering from sleep deprivation and was having a hard time focusing his attention.
In other words, it might not be a good idea to go flying right after a family tragedy or some other life changing event and you need to make sure that your passengers understand that any intense discussion beyond flying can wait until everyone is safely on the ground.