Hiroshi's relatives

Ginnosuke Nohara

Cool Old Guy: Despite his age, he can keep up with the new trends of the world and knows how to have a good time with his grandson.
Dirty Old Man: Like Shinnosuke, he enjoys looking at pretty young women, much to his wife's dismay.
Foil: Serves as this to Yoshiji Koyama, as he's open-minded, a bit childish, and is bald.
Hair Today, Gone Tomorrow: As shown in Hiroshi's memories in the Adult empire strikes back movie, he had short black hair when Hiroshi was a kid.
Like Father, Like Son: Like his youngest son, he often looks at young women in front of his wife.
Manchild:
The Rival: Due to their clashing personalities, he is often seen antagonizing Yoshiji Koyama

Tsuru Nohara

Cool Old Guy: Like her husband, she can keep up with the new trends of the world and knows how to have a good time with his grandson.

Semashi Nohara

Adaptational Late Appearance: He didn't appear in the anime until he finally appeared in the special episode "It's time! Semashi Nohara is here!"(野原せまし登場!だゾ), which was made during the 30th anniversary of the franchise.
Foil: To his younger brother, unlike him, decided to work as a farmer instead of being a salaryman, doesn't have Hiroshi's infamous smelly feet, and is still single. Later, he manages to marry a woman called Ikuna who had children before.
Meaningful Name: His name Semashi literally means stingy, as he's a miser who avoids spending money.
The Stoic: Unlike his younger brother, he rarely expresses any emotions.

Misae's relatives

Yoshiji Koyama

Foil: Serves as this to Ginnosuke, as he's serious, mature, and still has hair on his head
The Rival: Due to their clashing personalities, he is often seen antagonizing Ginnosuke
Not So Above It All: Despite being the most serious relative of the Noharas, he can sometimes lose it while competing against Ginnosuke.

Hisae Koyama

Masae Koyama

Cool Mask: During the times she visits the Noharas, she always introduces herself by wearing one just for the sake of scaring Misae.
Laser-Guided Karma: After scaring Misae, she is often scared by Shin's weirder masks when trying to prank him.
Kimono Is Traditional: Unlike her younger sisters who wear simpler clothes, she prefers to wear kimonos.
The Prankster: She loves pranking people, especially her younger sister Misae.

Musae Koyama

Annoying Younger Sibling: She's the youngest of Misae's sister.
Lazy Bum: During her stay at the Nohara's household, she barely did the bare minimum.
Put on a Bus: Her role in the series is reduced after she gets a new job as a photographer and moves to Matazuresou.