This girl has other issues dealing with personality, but like l told his mother, we'll have to let our son deal with them.
In the above example the two people are baptized Christians of different confessions (or denominations), but a non-baptized person is not a part of the Christian family.
When it involves someone who has not been baptized then the marriage requires an express dispensation from the bishop in order for the union to be considered valid.
The Catholic person must uphold the obligation to preserve his or her own faith and “ensure the baptism and education of the children in the Catholic Church,” (Catechism of the Catholic Church, 1635).
One of the reasons that the Church exists is to safeguard the souls of those in its care.
A marriage to a non-baptized person can be especially difficult because of the greater chasm in religious belief.