I echo the sentiment from my own experiences travelling with my (under two years old) son on BA.
One of the best I’ve witnessed was on a LAN flight from JFK to SCL, a couple travelling with a very new looking baby in J. The kid was awake and behaving well when the meal was served, but one of the crew was summoned by the purser and they offered to take the kid while the parents ate. The crew member’s face lit up when they accepted, and she spent the whole meal service walking up and down the plane cradling the child and quietly singing lullabies to it. As soon as the parents finished eating the kid was handed back and went to sleep. On arrival the parents spent a good few minutes talking to the pilot and crew member expressing their thanks, etc. It was beautifully handled all round.