Kayaks for the family
I'm biased toward Ocean Kayaks so I'll tell you what I would get. For the wife, I would get an OK Prowler 13. It would be easy enough for her to handle, but big enough for you to go by yourself. Overall, it is an excellent fishing platform. For the daughter, I would get an OK Venus (either the 10 or the slightly larger 11). This one even comes in pink.
After that it gets tough. Tandem kayaks and fishing are not the best fit. Few of them are set up for fishing. Ocean Kayak has three that would work, the Sidekick that is designed for an adult and a small kid, but it is really to small to be workable for fishing; the Malibu Two that would probably work for you, but again, not a great fishing platform; and the Zest, which is the aircraft carrier of the line up at 17'.
One other option I can think of is (and this is probably the best one) is a Malibu Extreme with the optional front gator hatch for a child. This is a great fishing kayak, although a little on the heavy side, but very stable. Since it is designed as a single, it would be good when you go out by yourself. Most tamdem kayaks, except the OK Malibu Two, do not lend themselves to single handing.
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