towing front wheel drive vehicle

Can anyone tell me if you need to lock the steering wheel when towing a vehicle on a tow dolly? We have a front wheel drive Toyota Highlander and are planning on towing it behind the RV on a tow dolly (2 front tires on the tow, 2 back tires on the ground). Some people said we need to lock the steering wheel, some say you shouldn't. Does it matter?