This update is dedicated to @geetarshi for guessing almost all the characters correctly 

Rakesh Singh Raizada

Hritika's husband

Alok's father

Juhani, Adarv, and Arnav's Dadu

Father figure to Nandini

Mentor to Yash 

Lawyer by profession 

Hritika Rakesh Raizada

Rakesh's wife

Alok's mother

Dadi to Juhani, Adarv, and Arnav 

Hritika is a housewife

Janki Alok Raizada & Alok Rakesh Raizada 

Rakesh and Hritika's son and daughter in law

Juhani, Adarv, and Arnav's parents

Friends of Ram and Arti

Alok is the Chairman of RG Corp. and Janki runs an NGO

Nitya Adarv Raizada & Adarv Alok Raizada 

Rakesh and Hritika's eldest grandson and granddaughter in law

Alok and Janki's eldest son and daughter in law

Juhani's twin brother and sister in law

Arnav's elder brother and sister in law

Best friends of Puja and Rohan 

Both work in RG Corp. 

Sanjay Sharma & Juhani Sanjay Sharma aka Juhi

Rakesh and Hritika's granddaughter and grandson in law 

Alok and Janki's daughter and son in law 

Adarv's twin sister and brother in law 

Arnav's elder sister and brother in law

Juhi is Mishty's best friend

Both Sanjay and Juhi work in RG Corp. 

Ram Pratap Gupta & Arti Ram Gupta 

Puja and Mishty's parents  

Lokesh's elder sister and brother in law 

Friends of Alok and Janki

Ram is the CEO of RG corp. and Arti is the principal of Gupta public school 

Rohan Raichand & Puja Raichand

Ram and Arti's elder daughter and son in law

Yash and Nandini's younger son and daughter in law

Mishty's elder sister and brother in law

Rahul's younger brother and sister in law

Arul's Chachu and Chachi

Both works in Raichand Constructions.

Yash Raichand & Nandini Raichand 

Rahul and Rohan's parents 

Arul's grandparents 

Yash was the Delhi high court judge and now is retired and Nandini is a homemaker

Rahul Raichand & Anjali Singh Raichand 

Yash and Nandini's elder son and daughter in law 

Arul's parents 

Rohan's elder brother and sister in law 

Rahul is a bureaucrat and Anjali is a dance teacher 

Arul Raichand 

Rahul and Anjali's son 

Yash and Nandini's grandson 

Rohan's nephew 

Lokesh Sahay 

Arti's younger brother 

Puja and Mishty's Mamu

Best friend and colleague of Chetan 

Teacher by profession 

Chetan Gogi

Vikram's younger brother

Best friend and colleague of Lokesh 

Colleague of Mishty

Teacher by profession 

Vikram Gogi

Chetan's elder brother 

Lawyer by profession 

Nishan Verma aka Shan & Gitika Verma aka Gitu

Arnav and Amy's best friends 

Shan is SP and Gitu is a freelance interior designer 

Adam John Lewis & Daisy Adam Lewis 

Danny and Amy's parents 

Adam is the Canadian supreme court judge and Arnav's mentor and Daisy is a fashion designer 

Daniel Edward Lewis aka Danny 

Adam and Daisy's son

Amy's elder brother 

Fashion designer and Model

Aman Lopez 

Arnav's personal assistant 

Narain Kashyap aka NK

Amy's personal assistant