Sayyid Ali Hussaini Sistani
Grand Ayatollah Sayyid Ali Husseini Sistani (born 4 August 1930), commonly known as Ayatollah Sistani, is one of the most powerful and influential Twelver Shia Marja in Iraq and the head of many of the hawzahs (seminaries) in Najaf.
Most prominent scholars among the students of Ayatullah Sistani or any other Marja' of Taqleed are not announced in public and it depends on the opinions of different leading scholars who evaluate those students and judge who are the most senior among them.
Quran is complete, intact and unchanged. This is the faith of leading Shia scholars including Ayatullah Sistani, Ayatulla Al-Khoei, Shaikh Al-Sadouq, Shaikh Al-Toosi, Sayyed Al-Murtadha, Shaikh Al-Mufeed, Shaikh Al-Tabrasi, Shaikh Kaashif Al-Ghitaa' and thousand of Shia scholars.
There are some Sunni narrations from Umar and Ayisha that Qur'an which is available in our hands is not complete (Saheeh Muslim 1050, Musnad Ahmad 5:132, Al-Mustadrak 4:359, Al-Kashshaaf 3:518 etc), with few weak narrations in few Shia books, but there is no values for such narrations. Our authentic evidence from Ahlul Bayt (AS) is unchallengeable that Qur'an is complete and intact.
They may pray together in one room. The husband has to pray in a position that is ahead of that of the wife.