How many crofting households are there in Scotland?
There are around 17,725 crofting households in Scotland
From Wikipedia: Crofting is a form of land tenure and small-scale food production unique to the Scottish Highlands and the Islands of Scotland. Within crofting townships, individual crofts are established on the better land, and a large area of poor quality hill ground is shared by all the crofters of the township for grazing.
As of 2006, the US Census Bureau reports a total of 77,402,000 family households. (The remainder are termed "non-family" households). Of this 77.4 million households, 30,201,000 do not have children of their own. 47,201,000 have children of their own. I did not research the number of households with someone else's children (for instance, relatives raising children, foster homes, etc.).