The one arrangement I haven't touched upon is the religious aspect. Our family (as in so many) runs the gamut of atheist/agnostic to profoundly religious.
Some of my readers may be from other parts of the world. I realize that there are variations in each major religion, with traditions and nuances that are difficult for outsiders to understand. I am not sure if any of the major religions have as many variances as those in Christianity. And among Christians themselves, those that call themselves "Protestant" seem to have a new sect or church for every possible variation of belief. I'm no expert, and this isn't a theological treatise. I'm not really trying to explain the differences here. Just mentioning how many there are among us.
Families grow up with religious labels, whether they regularly attend church or not. My mom grew up in a Protestant family, under the label of "Methodist". They rarely attended church. On her own she began attending a nearby Roman Catholic church. She converted on her own and began participating in the church through her teen years. She met my birth father at a dance there when she was seventeen. (My birth father died when I was six.)
My mother's mother (my grandmother) was respectful of her choice. Her own sister (my great-aunt) had married a Catholic and there had been some anger in the family about it. It was good that my grandmother was open-minded. Her oldest daughter married a Catholic and converted. A few years later, my mother married a Catholic too. This was an era of intolerance. It was still considered a terrible wrong for a Catholic and a Protestant to marry. Many Protestants looked down on Catholics with disdain. My grandmother's other sister had remained a staunch Methodist through her life. To her dying day this great aunt of mine would refer to us Catholic members of the family in derogatory terms.
When John F. Kennedy was running for President of the United States he had to launch a campaign to prove that although he was a Catholic, he wouldn't be a 'puppet' of the Pope if he were President. Even in the middle 1960's, my father's younger brother married a Protestant. He chose to convert to her church. It took years for uproar that rocked the family to die down. A large number of the older generation went to the site of the wedding, but stood outside the church. They were 'at the wedding, but not at the wedding'. (I've never understood the logic there). My mother, to her great credit, was a staunch defender of the young couple. Legend has it (I was too young to comprehend) that she gave quite a speech to those closed minded people as they stood outside the church.
When my birth father died suddenly, leaving my mom with four small children, she lost her faith. When she met my step-father (I call him dad) a few years later, she agreed to start going to church again. They were married in his Catholic church.
As our family grew older there were lots of splits. I have three sisters and a brother. One is Lutheran, one is Methodist, two are Evangelical Christians. I slip in and out of a Pagan/Catholic/Buddhist type belief of my own creation. I'm not a regular churchgoer. Every Sunday, dad still attends the same Catholic church he was married in. My mom quit going to church on a regular basis a few years after they married. The variations in our immediate family are the same in the rest of our family. Very few (I actually can't think of any off-hand) families of my aunts/uncles/cousins are all members of the same religious denomination.
My mom would occasionally attend one of her children's churches--primarily for some event. When she was in the hospital each of my siblings brought in their own minister to pray over my mom. They wanted her to have a religious service, but which religion? Fortunately, my mom had mentioned that she liked my brother's Lutheran pastor. Based on that, we decided that would suit her wishes. He agreed to help, and did a very nice job.