I live on the South end of lake O’Brien. If you like small to mid-sized Sun Fish the lake is great. The largest Sun Fish I have pulled out of the lake is about 10 inches. Any Sun Fish bigger than 8 1/2 inches I catch, I return to the lake as breeding stock.
There are some Crappies, I have a hard time finding them in the summer time.
There are large mouth bass of assorted sized and northern pike. None of them you would mount on your wall.
This is a small (less than 200 acres) recreational lake. The weekend are busy with Tubers, Jet Skis, and cocktail cruising pontoon boats. I limit my fishing time to mid-week when you have the lake pretty much to yourself.
I hope your family has an enjoyable week.