Kunan - I've been there..... We have two boys under two years. I use a backpack to carrying the eight month old while my wife looks after the two year old.

Try Drano Lake on the Washington side. There is good access along the road leading to the hatchery. There are alot of steelhead returning to the hatchery plus alot of upriver fish pull into the cool water of Drano Lake to rest if the mainstem Columbia gets too warm. Pitch spoons in the early morning for your best chance at a steelhead. Good luck!