I'm going to give the benefit of the doubt to Mom, because she...I mean they...I mean it...I mean that, probably has to generate an income due to a number of circumstances.So many warnings about pregnancy these days.
Do not smoke while pregnant, do not take Tylenol while pregnant, do not drink while pregnant.
Paint fumes and pregnancy is clearly not a good idea. Seems like a foolish risk to expose one's unborn child.
I would hate to be the employer in this situation. The mother is either in a position where she feels she must work, or is unconcerned about the consequences of her actions.
As an employer, and if this employee has been an asset to the company, I would have to find a way to accommodate them for the period of time they are pregnant. For example, maybe I could do something like have them do admin stuff such as inventory, sales generation, web maintenance, project management, time sheets, washing vehicles, purchasing and delivering sundries and paint, etc.
After they bare the child, there will have to be another discussion on availability of the employee due to child care, and how that impacts their ability to meet employee obligations.