I'm going to have to side with your wife on this one. There is absolutely nothing more precious than your child's life. Use one of the work arounds the other gave you above. Driving to the sitters and riding from there sounds like a good option.
Now, I know driving in a car is not 100% safe, but at least there is some heavy steel and more space between your child and danger. Anyone who does carry there child on a bike/trailer, please don't let this sound like I am judging you. I applaud you and wish you the best.
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