If two married Protestants both become Catholics, have they to be married again in the Catholic Church?

The Catholic Answers

No. They were both Protestants at the time of their marriage, and the Catholic Church declares such marriages to be binding before God. The law of the Church in this matter extends to marriages in which at least one of the parties is a Catholic.

Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty