Taking a second wife

Q: I am 35 years old. Married with children. I have decided to take a second wife. I told my wife everything that had happened and want to take a second wife, but she refuses to agree. I do know that I do not need her permission but I would like to get her permission because she is important to me. The second lady has read her isthikaara and has accepted to be my second wife, she fully understands the regulations of being a second wife. Could you please assist with my problem.

Finding some partical of food in one's tooth or some dirt in one's toe nail after ghusal

Q: I made gusal to become free of janabah. I made my ghusal washed properly but once gusal was over I dressed, done a few other things and then realised that something was in my tooth but it seems it was there before I made ghusal. I used a tooth brush while in ghusal but found nothing. This dirt was found in a deep whole of my tooth. What is the procedure if something is stuck on the side of my toe nail. What should I do and is my ghusal made?

Tafseer of Surah Nisa', verse 16

Q: Does this mean that don't punish them if they repent, Allah is of forgiving or punish them and if they repent leave them. Allah is of the forgiving (4:16)? And the two who commit it among you, dishonor them both. But if they repent and correct themselves, leave them alone. Indeed, Allah is ever Accepting of repentance and Merciful. (Sahih International)

Marrying one's cousin

Q: I have two uncles. My grandmother has breastfed my elder uncle's first child. Now my parents want me to marry younger uncle's daughter. So, is it permissible according to Islam as my grandmother has breastfed my eldest uncle's first child.