An interracial baby would not have left an impression so neither would it's mother. I was much too involved with my own baby to pay attention to another's.
So I doubt a woman with twins would have paid much attention to another's baby or for that matter, it's mother.
It's not a question of juding anyone, it's one of observation.
In those days, the babies were in the nursery most of the time. The mothers were in their rooms, usually two woman to a room, but sometimes it was a ward, with lots of women in the same room. Lots of time to talk, and observe the other ladies' visitors.