Heeyoung Byun.

Parents: Byun Namjin and Park Aeiyoung. Divorced. Sibling: Hyunjin Byun

Aeyoung Park married to Kim Taejoon.

Heeyoung's siblings:

- Taemi Kim married to Minho Choi

- Taemin Kim married to Saeyoung Byun

- Taehyung Kim

Byun Namjin married to Lee Boyeon - Half-Siblings: Byun Baekhyun married to Lee Jihyun and Byun Baekhee.

Cousins from Dad's side (Byun Clan)

- Yohan Byun

- Saeyoung Byun married to Taemin Kim.

- Choi Youngjae

- Choi Jungha

Cousins from Mom's side (Park Clan)

- Haejin Park married to Jiara Kim.

- Hyungshik Park

- Park Chanyeol in a relationship w/ Min Sunmi.

- Heechan Park married to Bomi Song.

Kim Jongin.

Parents: Choi Inhee and Kim Jaesuk

Siblings: Kim Jongdae engaged to Son Seungwan.

Cousins:

- Kim Minseok married to Doh Hyeri.

- Kim Junmyeon in relationship with Choi Seol, parents to Jayden Spencer Choi-Kim.

- Jiara Kim married to Haejin Park.

- Jihana Kim married to Eddy Jung

- Jaemin Kim.

- Go Mina and Go Minsup.

Oh Family. 

Oh Sehun married to Zhang Yiming, parents to Oh Miran and Oh Yibo.

Oh Sera is engaged to Jackson Wang.

Doh Kyungsoo married to Min Aejung. Children Doh Aera

Zhang Yixing in a relationship w/ Elle Jung.

Hope this is helpful, Kaira di.

I have no idea how to write out chacter summaries.

If you need more clarifying or if I forgot to add people, please let me know.