We set off on Saturday afternoon with Oliver in the new seat on the back of my bike and Mimi riding in front of us.
While we were waiting at a red light, a couple crossed in front of us with their child deep within a car-seat stroller.
'How old was your baby when you first put him in that seat?' the woman asked in a familiar way.
I said that he had been a week younger than he was now; Mimi gave his age and asked how old their baby was. Nine weeks, was the reply. A little early to be thinking about bike seats.
(Later that evening I noticed that the safety notice on the back of the seat said 'Child must be old enough to sit upright attended while wearing a helmet'.)
About 2 km into the ride, Oliver started to seem very quiet and when I felt the helmet against my lower back I knew he had probably fallen asleep.
We're going to try again tomorrow.