What if the baby is injured, by a child, or swallows something small? What if the baby is not always sound asleep, but teething, and is grizzly, noisy and ultimately distracting?
At least one parent has said their child's reading has suffered, and has moved schools, which could not have been an easy decision to make.
Others have praised the school for its modern open-minded approach.
What's wrong with kids learning in an environment with a young child about? Doesn't that teach children about life? Not to mention how liberating it must be for a qualified teacher to be free to do at least some of what she's trained for and, presumably, loves.
Both are valid points of view and, not surprisingly, social media reaction has been divided. But slightly more supportive.
And we agree.
It's a matter of where you draw the line. No, police officers are out but, in these circumstances, perhaps that line has not been crossed. Different if the position was full-time, perhaps.
That is not to lessen the concerns raised by some parents, and the position warrants close monitoring.
Where the school may be faulted is that it did not consult its parents early enough about the presence of the infant in class.
Nor did it respond satisfactorily to concerns raised, if indeed, it did dismiss those concerns somewhat summarily.
Last word goes to the teaching mum.
Feel great about yourself. The publicity has not been about you, but about a fascinating issue that might be evidence of us growing up a little as a society.