As the numbers of the Quakers shrank, it became more and more difficult for the young people to find proper mates among their faithful. Yet, they got in trouble for marrying cousins. Many of these young people were written out of the Quaker faith for not marrying "in unity." This happened to several of my ancestors.
If they weren't expelled for marrying out of unity, they were for supporting the revolution. Such was Captain John Harper who married out of unity and smuggled ammunition for Gen. George Washington aboard his ships among other things. He had grown up squirming in the pew in a Quaker meeting house in Philadelphia but was expelled later for marrying a non-Quaker.
Nowadays the Quakers have welcomed just about anybody of any faith into their fellowship. The guide in one of the early Quaker Houses in Philadelphia was a little surprised that they would have written anyone out of her beloved church. I, myself, almost had to leave because of the heavy smell of her cigarette smoke. Now that's how to make 'em roll in their graves as good Quakers should...wait, many of them grew tobacco! Well, maybe the smell of it didn't bother them as much as it does me. Who knows?