Shame the Spot died - one idea might be to locate the Spot pen out in deeper water in the bay itself.
Often this time of year - oxygen levels can drop very low in the creeks. Combine that with high water temps. and Spot can die.
Funny you are getting your father into fishing - 99% of the time it's the other way around.
This will make more sense as you get older but do your best to fish with your dad as much as you can.
What could be more mundane than dying of old age or of natural causes when there is death by misadventure to be pursued ? Skip