Tanjiro: Middle brother: Takes care of the house and basically does most of the chores

Inosuke: Youngest brother: Spends all his time playing outside and picking fights with his brothers

Zenitsu: Nezuko's boyfriend: Don't kill me, I ship this because Zenitsu is actually kind of sweet. Besides, he's a low-key badass

Nezuko: Youngest sibling: Helps Tanjiro with his chores and takes care of grandparents.

Kanao: Tanjiro's girlfriend: Studying biology in University to become a doctor. Frequently stops by the house.

Giyuu: Oldest brother: Almost no friends, studying to become a teacher.

Shinobu: Giyuu's childhood friend/bully: Everyone ships them, which annoys her.

Tengen: Older Uncle: Gets along really well with Inosuke and play/fights him whenever he comes over.

Rengoku: Dad: Everyone likes him and he's always got a word of encouragement to give. He helps Inosuke and Mitsuri get through school by helping them study

Iguro: Mitsuri's boyfriend: Doesn't like the rest of the family very much, but he is very helpful

Mitsuri: Oldest sibling: Wants to be treated like the youngest and frequently acts like she is. Loves playing with Nezuko rather than studying, which causes some problems.

Gyomei: Grandpa on dad's side: Ridiculously strong for an old man

Muichiro: Cousin: Doesn't say much at family reunions, but gets along very well with Tanjiro. He's a surprisingly good cook.

Shinazugawa: Younger Uncle: No one really likes him, but he's tough and has protected the family more often than not. If only he were less aggressive.

Bonus:

Genya: Youngest cousin: Everyone likes him. He's shy around any girl, including his siblings, which makes it kind of rough for him

Urokodaki: Grandpa on mom's side: Nezuko loves playing with him and he spoils her.

Aoi: Inosuke's guardian and childhood friend: She looked out for him, and was inadvertently pulled into the family, almost against her will, but she ended up having fun.