Syed: As our beloved Prophet have 11 wives and are known as “Ummahat-ul-Momineen” which means “Mothers of the Believers”. From them, Hazrat Khadija was his first wife. Fatima bint e Muhammad (Bibi Fatima) was the daughter of our beloved Prophet Muhammad SAW and his wife Hazrat Khadija. She was the dearest and beloved child of Muhammad SAW among all and she was married to Hazrat Ali also known as Mola Ali.
Hazrat Ali and Bibi Fatima have five children; Hassan ibn e Ali, Hussain ibn e Ali, Mohsin ibn e Ali, Zainab bint e Ali and Um e Kulsoom bint e Ali.
From this family, Prophet Muhammad SAW said, I’m Syed, my daughter Fatima is a Syed, my son in law Ali is a Syed, my grandsons Hassan and Hussain from Fatima and Ali are Syeds and the whole generation of my grandsons Hassan and Hussain are Syeds.
He told his followers to respect his family (Syeds) and don’t hurt them. Even that the fire of hell is haram on Syeds. Following are some of the hadiths:
Love me for the sake of Allah and love my family for my sake.
(Tirmizi, vol. 5, p. 434, Hadees 3814)
I swear by the One in whose Power my soul is, whoever hates my Ahl-e-Bayt, Allah Almighty will make him enter Hell.
(Mustadrak lil-Hakim, vol. 4, p. 131, Hadees 4771)
My intercession is for the one in my Ummah who loves my Family.
(Jami’ah Sagheer, p. 301, Hadees 4894)
Females of Syed Families are not allowed to marry someone else from another cast as they are said the mother of believers. Nikah/Marriage of syedzaadi is Haram with a non-syed. There are many books of different writers, some of them agree to this and some of them totally disagree as per Shia and Sunni issues.