The film will also be the Bollywood debut of actress Saiyami Kher, the granddaughter of yesteryear's leading actress Usha Kiran and niece of Tanvi Azmi.
"The kind of hard work Harsh puts in is incredible. We all work hard, but he is very idealistic about his work. He is very intelligent and sharp. He will go a very long way," Sonam told PTI in an interview.
"It is not like he will be the superstar, and filling in the cinema halls. But he will be a force to reckon with when it comes to talent and choice of films," she said.
"Mirziya" is inspired by the love tale of Sahiban and Mirza, and is described as its contemporary adaptation. The screenplay of the film is written by Gulzar.
The "Neerja" actress, who is known for speaking her mind, said in her family they all have been given freedom to evolve and have their own opinion.
"He (Harsh) will do different things (in films). We all have been brought up with a strong sense of individuality. We have been given space and freedom to evolve," she said.
The 30-year-old actress, who is basking in the success of her latest release 'Neerja', said she has taken her career decisions by herself and never involved her family, including father Anil, in any of the matters.
"I don't listen to him (Anil Kapoor). I don't listen to anybody. I do take his advice, but it is up to me whether to take it or not. I would rather not have them involved in my professional life as I think it is not fair," she said.
Anil Kapoor had once candidly mentioned that with three actors (he, Sonam and Harshvardhan) in their home, there is in-house competition.
"There is no competition. I think it is about competition of getting my mom's attention," Sonam joked.
