In Japanese, there are certain nuances to consider when talking about your
"Son" can be translated to "息子" (musuko) in Japanese.
In Japan, children call their parents Dad and Mom, or other words to that effect. Older siblings are also called by position. Fathers and mothers do call their own children by name only. “Mio, time for dinner!”
The Japanese language contains many loan words from English. Mama is one of them, and as it is a more child-like word, it is typically used by children. It is also written in katakana (ママ). When children grow older, they start addressing their mom as okaasan.
Chichi (父 / ちち) is the humble way to say father in Japanese. It is typically used when speaking about your father to somebody else. It can also mean father in a general context, like how it is used in chichi no hi (父の日 / ちちのひ) or Father's Day. Example: Chichi wa byouin ni tsutomete iru.
In general, -chan is used for young children, close friends, babies, grandparents and sometimes female adolescents. It may also be used towards cute animals, lovers, or youthful women. Chan is not usually used for strangers or people one has just met.
In Japanese, names go "Surname - Given Name". So, if your name was "John Smith", they'd call you "Smith John". Goku, Gohan, and Goten all have "Son" in front of their names because its their surname. It's their "Last" name so to speak.
Unlike many western cultures, in Japan people generally don't call one-another by their first name. Doing so can be a mark of disrespect, unless you're very close to the other person and in the right sort of casual environment, so you've read. Mental note then: first names are best avoided.
Musume. The word musume (娘 / むすめ) is typically used when talking about your own daughter in polite situations. However, you can use it for somebody else's daughter by adding the honorific suffix -san (～さん). Watashi no musume wa hikoushi ni naritai desu.
Danshi is a standard way to say 'boy' in Japanese.
Danshi can also be a word for males in general though, and is often used on toilet signs to show the male toilets (danshi toire / 男子トイレ or just danshi / 男子). Danshi is a combination of two kanji, dan / 男, meaning 'male' and ko / 子 meaning 'child'.
A very familiar term, "~ chan （～ちゃん）" is often attached to children's names when calling them by their given names. It can also be attached to kinship terms in a childish language.
The first son would be known as "Ichirō", the second as "Jirō", and so on.
-Kun is the more respectful of the two, but is still rather informal. It's used more commonly for men and boys than women and girls. That said, it's become more common for higher ups to refer to juniors at work using -kun regardless of gender and for teachers to simply use -san for everyone, regardless of gender.
Kun (君) is informal and mostly used for males, such as boys or juniors at work. It is used by superiors to inferiors, by males of the same age and status to each other, and in addressing male children.
Oniisan. Oniisan (お兄さん / おにいさん) is one of the popular, polite ways to say big brother in Japanese, although it is often used in two specific situations: when speaking to your older brother and when talking about somebody else's older brother.
Hookups and Casual Dating are Taboo
Yet even the people that don't share this opinion also. The same can be said for casual dating, even something as small as kissing your date is shunned upon. Only when you are officially in a relationship should you be able to kiss each other.
Japanese law requires that married couples share the same surname, which can be that of either the husband or the wife. There appears to be no country other than Japan that requires married couples to adopt the same surname.
Unless you've been invited to use first names, then it's polite to stick to surnames only. Jumping to first names too quickly might well be deemed as presumptuous (and even offensive if the person is more senior to you in age or position).
It's quite an affectionate word, which might be used with a friend, a classmate, a little sister, a baby, a grandmother, a girl or a woman to let her know you think she is sweet. "-chan" can also be used with little boys; though from adolescence, it becomes rather feminised.
In these circumstances, when a baby is born between spouses with different last names, child's surname in Japan will automatically be the last name of the Japanese parent in official Japanese government records (koseki tohon).
Chan (ちゃん)
Chan, the childish version of san, refers to children and girls.
The most common way for Japanese guys to call their girlfriend is simply to use their first name, either by itself or with the suffix -chan. In Japanese, you would never call someone you don't know well by their first name without an honorific suffix such as -san or -sensei.
Sama (さま) is the respectful version of san, mostly used in business and clientele contexts, for people of higher rank, or somebody you admire. This is because the implied superiority of the guest or customer is very strong. Sama is gender-neutral just like san.
You wouldn't generally refer to a woman as “kun” under any normal circumstances. The generally accepted analogue for women is “chan,” but you should be careful not to refer to someone as either kun or chan until you get to know them enough first.