Well, I hope the kids aren't too whiny about walking, but once you've tackled the long block from Saulter to the Don Roadway, you're at the new part of the river. Either cross the river on the colourful bridge and follow the riverside trail south and west, or don't cross, and just take the first trail south and west along the river from there. There's a pedestrian bridge over the river about 85% of the way to Cherry where you can cross to the other side and make your return that way, or turn around before that if the kids' timers are running low.
42