Making taubah for sins

Q: I was listening to one of your recordings. I came to know that we should not talk about sins in detail when making tawbah.. have I understood correctly? If I mistakenly backbite shouldn't I say forgive me for backbiting..or forgive me I couldn't pray fajr today? I am not clear. Can you explain?

Population control and family planning

Q:

1. Is there any ruling in Islam regarding population control. Nowadays there is a drum beating of population explosion that the earth cannot sustain more than 10 billion people. Also due to sanction countries like Iran, North Korea, Yemen, etc. that cant provide education and health to all. Please help explain what is the way forward if population control via family planning is not an option?

2. Can the couple decide that we will limit our offspring and is that Islamically correct?

Forcing someone to perform nafl salaah after Maghrib azaan

Q: In our locality in the middle east, all local people pray Tahiyyatul Masjid between azan and Maghrib and those who don’t pray are sometimes instructed to pray and not to sit without praying; but on the other hand, there are people from India and Pakistan who say if you will pray, our children will get confused and think it is ok to pray at this time. What should we do in this situation? Pray or go in the Masjid and sit waiting for Maghrib prayer?

Maximum period of nifaas

Q: I have a few doubts regarding a woman's impurity after child delivery. I request you to please provide all answers with references so that I can educate my wife and other dependent ladies at my home

1. Exactly how long does a woman remain impure after child delivery? There is an old woman's saying that 40 days is the minimum period. If a woman's bleeding stops after 7 days, but she has irregular bleeding every alternate day or once in 3 days, what will the period be?

2. After the impurity period, can she do everything like praying, reading Quran and physical relationship with her husband?

3. Does she have to make up for the missed prayers during her impurity?