I am a 21-year-old Shi’ah muslimah from a Sayyid family who is in love with a non-Sayyid Sunni man who wants to marry me. Although his parents agree to this, my parents disapprove. They claim a Sayyida should never marry a non-Sayyid. Is it true that a Shi’ah muslimah should not marry a Sunni man? Is that considered a sin?
I have lived with my foster parents since I was one year old, and consider them my real parents. While my biological parents do not know anything about my marriage intentions, my foster parents are completely against it. Please guide me as I have decided that I will do whatever my religion permits.

Before answering your question, we would like to clarify three rulings in Islamic Law:
1. There is no objection whatever to a Sayyida marrying a non-Sayyid.

2. If a Shi’ah lady marries a Sunni man without weakening her faith, that is her husband accepts her right to remain a Shi’ah muslimah, there is absolutely no objection to such a marriage.

3. Only a biological father has the right to object and withhold his consent to his daughter’s marriage. Foster parents do not have any such authority.
How did you come to be in love with and so close to the young man you write about if you are a devout Muslim lady? How, without misbehaving, can a well-behaved young woman ‘fall in love’ with someone without her parents’ knowledge? Falling in love is not simply fancying the look of someone? Are you confusing attraction with love? Why did you not elicit the help and guidance of your foster parents when you felt your emotions were being stirred? Having explained the above, you may, according to Shari’ah, marry the man of your choice, but the support of your foster parents is quite another matter.