Please bear with me, its not totally how it sounds...
Since my DS was born me and my partner have always put him in his pram just before bed time and gone on a very long walk. He would then fall asleep. When we got back we would put him into bed.
We didn't do this to get our DS of to sleep. We did this for exercise.
When my DS2 was born a few months ago, DS1 was too big for a pram, so we bought a step however he quickly outgrew this. Therefore the evening walks dwindled out as he couldn't keep up with the walks.
Now that the long walks are drawing in, with me and my OH be U to buy a double pram. We have seen a cheap one in a charity shop. It has a seat at the front and one at the back. You would not be able to see DS (4,nearly 5) sat in the back, drifting of to sleep under a blanket.
He is happy to do this as on holiday when he was tired a couple of nights he climbed in the pram on the way home and we carried baby back to the apartment.
We read him stories all the time and the bedtime routine would still happen...bath, teeth, pjs, but he would just climb into the pram.
Me and OH can't afford the gym membership but really want to do abit of exercise and its nice to go out on a walk at night and have a chat together. Also I rely on relatives for childcare in the day so can't really ask anyone to have kids at night whilst we go out for our hourly walk.