How real life relations changed in reel life

Let's see how relationship changes in reel life, when real life family members acted in the same movie:

Shahid Kapoor - Pankaj Kapoor 
Real Relation: Son-Father
Movie : SHAANDAAR (2015)

 Shahid played son-in-law of Pankaj Kapoor in the movie

Shahid Kapoor - Sana Kapoor
Real Relation: Half-Brother & Half-Sister
Movie : SHAANDAAR (2015)

Shahid plays the love interest of Sana's sister played by Aaliya Bhatt.
So, she is basically sister-in-law (saali) of Shahid in movie.

Randhir Kapoor - Rishi Kapoor
Relation : Brothers
Movie : HOUSEFULL 2 (2012)

In the movie, they played half-brothers.

Ajay Devgn - Tanuja
Relation : Son-in-law & Mother-in-law
Movie : SON OF SARDAAR (2012)

In the movie, Tanuja plays the role of Granny of Sonakshi Sinha, the beloved of Ajay Devgn.

Akshay Kumar - Dimple Kapadia
Relation : Son-in-law & Mother-in-law
Movie : PATIALA HOUSE (2011)

Akshay Kumar plays the role of son of Dimple Kapadia.

Amithabh Bachchan - Abhishek Bachchan
Relation : Father-Son
Movie : PAA (2009)

In movie, real life relation gets reversed. Abhishek dons the role of father of Amitabh.
At that time, Guiness Book of World Records also mentioned them as only father-son duo to play son-father role in any movie.

Arbaaz Khan - Amrita Arora
Relation : Brother-in-law & Sister-in-law
Movie : HELLO (2008)

In movie, Arbaaz Khan was husband of Amrita Arora.

Jaya Bachchan - Abhishek Bachchan
Relation : Mother-Son
Movie : LAAGA CHUNARI MEIN DAAG (2007)

In the movie, Abhishek loves the daughter(Rani Mukherjee) of Jaya Bachchan. So, she is mother-in-law of Abhishek.

Amitabh Bachchan -Aishwarya Rai
Relation : Father-in law & Daughter-in-law
Movie : HUM KISISE KUM NAHIN (2002)

Aishwarya Rai plays the role of sister of Amitabh. But, the movie was made before the marriage of Aishwarya with Abhishek Bachchan.

Salman Khan - Arbaaz Khan

Relation : Brothers
Movie : PYAR KIYA TOH DARNA KYA (1999)

In the movie, Arbaaz is brother of Kajol whom Salman loves. So, Arbaaz is brother-in-law (saala) of Salman in the movie.

Anil Kapoor - Sridevi
Relation : Brother-in-law & Sister-in-law
Movie : JUDAAI (1997)

Sridevi plays the role of wife of Anil Kapoor in the movie. Although, they had worked together in different movies during their career span. But, this was the last movie together after Sridevi married Boney Kapoor in 1996.

Sanjay Dutt - Kumar Gaurav
Relation : Brother-in-laws
Movie : NAAM (1986)

In the movie, they were brothers.

Shammi Kapoor - Rajeev Kapoor
Relation : Uncle-Nephew
Movie : EK JAAN HAIN HUM (1983)

In the movie, Shammi Kapoor was father of Rajiv Kapoor.

Shammi Kapoor - Rishi Kapoor
Relation : Uncle-Nephew
Movie : PREM ROG (1982)

Shammi Kapoor plays the role of father to Rishi Kapoor.

Shashi Kapoor - Rishi Kapoor
Relation : Uncle-Nephew

Movie : DUNIYA MERI JEB MEIN (1979)

In this movie, Shashi Kapoor & Rishi Kapoor  were brothers.

Randhir Kapoor - Nitu Singh
Relation : Brother-in-law & Sister-in-law
Movie : KASME VAADE (1978)

In this movie, they were love birds. Although, at that time Nitu Singh was not married to Rishi Kapoor. She married him in 1980.

Shammi Kapoor - Randhir Kapoor
Relation : Uncle-Nephew

Movie : MAMA-BHANJA (1977)

In this movie, Shammi Kapoor was brother of Randhir's mother i.e. he played maternal uncle to Randhir Kapoor.

Shashi Kapoor - Rishi Kapoor
Relation : Uncle-Nephew
Movie : KABHIE KABHIE (1976)

In this movie, Shashi Kapoor was father of Rishi Kapoor.

Shashi Kapoor - Nitu Singh
Relation : Uncle-in-law & Daughter-in-law
Movie : DEEWAR (1976)

In this movie, they were lovers. But, again, at this time  Nitu Singh was not married.

Sunil Dutt - Nargis
Relation : Husband -Wife
Movie : MOTHER INDIA (1957)

In this movie, Sunil Dutt player the role of younger son of Nargis. After the movie, they tied knot in 1958.
Also, Rajendra Kumar who played the role of her elder son, later became her relative. His son Kumar Gaurav gets married to Nargis' daughter Namrata.