Not sure from your post whether you were travelling with an infant, or if you were displaced by someone who was. Anyhow, in MMB if you select an exit row you have to tick that you have read and accepted the following:
Originally Posted by BA
You have chosen a seat in an emergency exit row
In the unlikely event of an evacuation you will be expected to assist in the opening of the emergency door. For this reason you must be an able-bodied adult (16 years and over) in full fitness and able to understand instructions given in English.
I declare that I am an able-bodied adult (16 years and over) in full fitness, able to understand instructions given in English and accept the responsibility attached to sitting in an emergency exit row. (tick box requiring consent)
We reserve the right to move you to a more suitable seat if we believe it is necessary.