This is the only "Night Before Christmas" illos I've seen in which the kids and their parents are sleeping in the same room. The living room, from the look of it. The title page typography reminds me of the earliest days of computer type, when everyone crammed as many fonts as they could into every page.
Did houses in New England have more than one fireplace? I'm guessing that, back then, during the coldest nights, the heat from the kitchen stove and single fireplace was too dissipated to warm any bedrooms enough for decent comfort enough to sleep through the night. So, during such nights in November through February, people not wealthy enough to have really solid, thick insulation and 2 or 3 fireplaces, slept all together, in the same room as their fireplace, close enough to the house's major heat source to be warm enough to sleep through the nights and remain as healthy as possible.
In any case, some of the poorer families had only one big "living room", and a kitchen, and perhaps, a storage pantry area near a back door. So, they had no "bedrooms", as such. And, having all family members in one single room, allowed them to share their body heat, as well, which might have helped them sleep through the night with one less time of leaving bed needing to add more wood to the fire.