I am changing your question to "Why did Catholics traditionally tend to have large families" from "Why do Catholics have 13 kids" because that is the question I presume you intend to ask.
Traditionally Catholics have had large families because contrary to what secular society claims, children are a natural and desirable by product of the love between a husband and a wife. In the first book of The Bible, Genesis, we learn that God commands Adam and Eve to be "fruitful and multiply, to fill the Earth and subdue it." The EXCEPTION to the rule, therefore is a small family. In short, couples who for medical reasons cannot have children, or for grave reasons need to refrain from having children are the exception to the rule, not the rule. The NORMAL course of action for married couples is that they should children. They should "be fruitful and multiply."
Couples who for grave reasons cannot have children cannot use Artificial Birth Control in good conscience. It's use is considered to be sinful because it distorts the workings of the human body. Through it's use a married couple essentially says to each other "I love every part about you but that part that can create life." It's use also implicitly takes the marital act and makes it more about pleasure and less about a self gift and a gift of true love. The Catholic Church embraces "Natural Family Planning" as a moral means to refrain from having children.
The Catholic Church, and therefore those in union with her see large families as a good, something desirable. Bringing people into the world to share love and life, rather then pursuing wealth and material things that cannot love a person are what matters to Catholic families. Money is great, careers are great, but in the end children bring love, money and careers do not.
They aren't necessarily. Catholics, who officially disapprove of birth control, tend to have large families. What one usually observes is that people in poor countries have larger families because where social support systems are weak, children are the "social security" system.
They can live in small or big families. I come from a family of 8, but there are still small families in the USA.
It all depends. Usually, the Bishops will encourage Catholics to vote for pro-life. However, there are the liberal Catholics who tend to vote Democratic. Yet, overall, Catholics tend to vote Republican.
Families of elements on the periodic table tend to have similar properties because they share the same valence electron configuration. This dictates the type of bonds the elements will make, which has a large impact on the chemical and physical properties of the element.
Mexico is reaching a demographic transition, where families tend to be smaller. Nowadays most families in Mexico are composed by both parents and one up to three children. Current fertility rate is 2.27 children per woman (2015 est.)
India has a large population due to factors such as a high birth rate, improvements in healthcare leading to lower infant mortality rates, and the country's cultural preference for larger families. India's population growth is also influenced by its history, geography, and socio-economic conditions which have led to a rapidly growing population over time.
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Traditionally it is the first wife however most families who practice plural marriage tend to be more democratic then that. There are some fundamentalist groups that have a strict order of authority often with the "legal" wife being in charge and that isn't necessarily the first wife.
Catholics generally think that anyone who is not Catholic is damned to eternal suffering in hell. This includes every non-Christian religion (Islam, Judaism, Hinduism, etc.), as well as non-Catholic Christians (Protestants). However, most Catholics don't get mad at anyone who isn't Catholic. In fact, they tend to pity them and try to warn them about what will happen if they don't become Catholic. Non-Catholics tend to hate it when Catholics try to convert them like this, but the Catholics see themselves as saviors.
Many families with young children tend to have a lab.
*This is generalising* The two main cultural groups in Northern Ireland are Protestants and Catholics Protestants: Political view= unionist/loyalist Nationality= British Catholics; PV= nationalist/republican N= Irish Protestants tend to play rugby, cricket, football Catholics tend to play Gaelic Football and Hurling, Protestants support Glasgow Rangers FC Catholics support Glasgow Celtic FC Protestants vote for DUP & UUP Catholics vote for Sinn Féin & SDLP Protestants live in east Belfast Catholics live in west Belfast Protestants go to state run schools Catholics go to Roman Catholic schools Protestants are in the Orange Order Catholics are in the GAA Protestants celebrate the Orange day (12th July) Catholics celebrate Easter Rising Catholics speak Irish as their 2nd language Protestants speak Ulster-Scots as their 2nd language Protestants wear a poppy to remember their fallen Catholics wear a lily to remember their fallen Protestants regard the IRA as terrorists Catholics regard the IRA as freedom fighters Protestants fly the Union flag Catholics fly the Tri-colour flag Protestants call the 2nd largest city 'Londonderry' Catholics call the city 'Derry' Protestants refer to 'Northern Ireland' Catholics refer to 'the north of Ireland' Catholics eyes are meant to be closer together Protestants say ee-ch for the letter H Catholics say he-ch for the letter H Protestants call Catholics; fenians or taigs Catholics call Protestants huns Protestants see Ian Paisley as their leader for unionism; Catholics see Gerry Adams as their leader for Irish nationalism Protestants read the Newsletter Catholics read the Irish Times Protestants tend to be more right-wing. DUP are anti-same-sex marriage, anti-abortion, conservative Catholics tend to be more left-wing. Sinn Féin are pro-same-sex marriage, pro-abortion, liberal Young Protestants are in flute bands Young Catholics do Irish dancing Protestants see the Queen as their figure head Catholics see the Pope as their figure head Catholics have larger families because of disapproval of contraception. *These are just stereotypes that I have just grown up with and do not apply to the majority of people here. Just a bit of banter.
The number of people at the average Thanksgiving dinner in a community depends on the size of families and their extended families, as people tend to eat Thanksgiving dinner with their families.