I have been precisely in your situation these past nine years. I built a drift boat while tending my infant daughter. Saw plywood, make bottle, change diaper, saw plywood, etc.
After she got older, I started taking her out fishing with me. Not very productive, but lots of fun. Lake Washington and Potholes reservoir were prime destinations, for perch and sunfish.
Then as she got older I would take her on short expeditions. Again, catching fish can't be the goal, having fun is. A good destination is one of the hatcheries when the fish come in.
I knew that this was all working when the following happened. I took Kate out to one of my cutthroat spots, and put her in the front with a rod with a little bit of roe on it while I cast a fly to the cutthroat slot. She caught 3 smolts, all carefully and safely released (barbless hook) while I managed one measely searun. I then had to listen to her brag to anyone that would listen that she caught three fish, and dad only caught one, at the very end.
I got the best christmas present one could ask for last year when I took her out plunking for a few hours on the Sky Christmas day, and she caught her first steelhead.
Now, my little guy, her younger brother, he looks like he might REALLY turn into a fisherman. But he's got a few years yet to grow into it.
So, I haven't been really responsive to your questions. Let me try to do that. I focus very tightly on a few rivers, and work on learning them well. I have believed for a long time that a few holes learned well will do you a lot better than driving to every river in the state. We are fortunate to live within easy driving distance of some good bank fishing rivers. I have done well on those, but prefer fishing from a boat.
If you can afford it, your son is probably getting to the point where he'll like fishing from a boat. My five year old digs it, though he doesn't yet have the patience for a long day. But that will come.
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