Do not allow your children to marry a child of a faith other than Christianity. Your grandchildren (and possibly your children) will stand a greater chance of converting to a lesser faith or worse, becoming atheists and satan worshippers.
Your children must be raised to understand that only Christian men and women should get married and that all other faiths are false religions and perversions of them.
People argue that the Lord God has multiple names and other religions simply call them by other names. This is not true. The Lord God has one name and we dare not speak it. Other gods are false gods, heathen gods and do not exist.
Marriage is a sacred moment in the eyes of God and it must be treated seriously. We cannot bastardize it by having half-Christian-half-Hindu weddings. You can't have half a blasphemy. This is a whole blasphemy.
If the man or woman in question to marry your child is of another faith they must be converted to Christianity and tested to make certain their faith is real.
If their faith in not true he or she will quickly lose their temper during the testing process (or object to being tested period) and this will be a sign that you must refuse to bless their wedding. You must prevent your children from making such a mistake at all costs.
Otherwise they will be doomed to a lifetime of blasphemy and an eternity of Hell for forsaking the Christian faith.