If you expand criteria a bit, there are succesful combos.
Salim Khan was a successful writer and Salman is super successful
Javid Akhtar was successful writer and both his kids Farhan and Zoya are quite successful
Jackie Shroff was successful and so is Tiger.
Privithiraj Kapoor, Raj kapoor, Rishi Kapoor, Ranbir, Shashi Kapoor, Shammi kapoor.
Dharmendra and sunny Deol.
Jitendra and Ekta Kapoor-not as actor, but she is a tycoon.
Yash Chopra and Aditya and same for Karan and his dad.
Nargis/Sunil Dutt-Sanjay Dutt.
But yes lots of failure combos- Amitabh/Jaya Bachhan -Abishekh who got to marry Aiswarya too!
Dharmendra-Bobby but he married some tycoon's daughter and is very rich.
Shammi and Shashi kapoor's kids did not make it.
Dimple and Rajesh kids-but Twinke married Akshay and is living high life!
Sharmila Tagore-though Saif is not a failure, but his sister didn't make it.
Mahesh Batt-Aliya mad eit and so did Pooja for a bit, but his son -wasn't he accused of being a terrorist.
Rajendra Kumar-one hit wonder son, married Sanjay's siter.
Hema Malini kids and probably Sridevi kids -nothing looks wise-hema's kids married and settled with families. Hoepfully Sridevi's kids do the same and not end up liek Boney's first two kids.
Rekha never had any kids-her father was a famous southern superstar-gemini ganesan though.
All the original Khan kids-Sanjay/Feroze khan etc never made it. Susanne married and divorced Hirthik.
Manoj Kumar and Dev Anand-nobody knows about their kids and one wonders if Dilip Kumar had any kids.
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