I think like others have said, that the MARRIAGE comes first.
In saying that, I mean that the needs of the husband, the wife, and the children must fit within the purpose of the marriage. A marriage entails the procreation and education of children and also the mutual nurturing of the husband and wife.
The point is, it’s not that the husband and wife should be choosing between the other spouse and the children. They have to chose the marriage about all. Sometimes meeting the needs/wants of the other spouse is the best way to serve the marriage. Sometimes meeting the needs/wants of the child is the best way to serve the marriage. Sometimes meeting his/her own needs/wants is the best way to serve the marriage. Most times it is probably some sort of compromise.
Those various needs of a marriage will change over time.
Newlyweds will hopefully have lots of time for mutual companionship and nurturing. And that will probably lead to some procreating (which for most people doesn’t involve much additional time.)
Couples with very young children will probably spend the majority of their time educating their children. I consider feeding and cuddling to be part of that education. So the time for one on one companionship between husband and wife is going to be limited.
As the children grow, the parents will be training those children that they need to be sensitive to the needs and reasonable wants of others, including parents, other siblings, extended family, and those outside of the family. Most such learning will be by experience. One of the biggest lessons for the children (and this will include those supposedly grown up children known as the parents) is the distinction between needs and wants.
Once the children become more independent, the parents will have more time to devote to their mutual companionship again. The children will hopefully be learning about how to be good husbands, wives, friends, employees, etc., by watching what the parents do in order to get by.
There’s no getting away from the fact that some of the ways this plays out are cultural. There are better and worse examples of doing things in almost all cultures.