Possibly relevant point: I believe there was a quiet room and Katie took Andromeda to the quiet room, but the room was not as soundproofed as they thought it was and she could still be heard.
(I am another person who considers the tone this is being brought up in to be highly unkind.)
I don’t actually think that parents have a huge amount of influence over the behavior of a person who is two months old. (I mean, it’s unclear whether parents have much influence over the behavior of a child of any age, but the case of two-month-olds seems particularly clearcut.) It seems unfair to praise them for the coincidence of Merlin happening to be sleepy at the time.