I’m guessing pbbth may not have a baby either-- I’ve never known an infant to sleep only during certain hours of the day.
I’m also skeptical of the “working an odd shift” requirement for quiet neighbors. I work the night shift, and unlike most of my daywalking brethren, I’m well aware that the entire world doesn’t share my shift. In fact, I rather like it that way. If the price of shopping an empty grocery store, perusing a quiet toy department, and eating a leisurely uninterrupted 5AM breakfast on my day off is that my neighbors will probably mow their lawns while I’m sleeping, I’ll gladly pay that!
Of course, I have an idea of what times I’d likely think appropriate to mow the lawn (if I had a lawn)-- probably between 8am (earlier is too early) and 8 or 9pm, depending on the time of year and the neighbors. On the other hand, I wouldn’t think badly of someone else for starting earlier, especially if they were sensitive to heat or sunlight, or had a job that prevented them mowing in the evenings.