The community has no less a role with baptized Christians seeking complete initiation that with catechumens.
403. Just as it helps catechumens, the Christian community should also help these adults by its love and prayer (see RCIA 4, 75.2) and by testifying to their suitability when it is time for them to be admitted to the sacraments.
The baptized newcomers also have sponsors, people to exercise the ministry of companionship:
404. A sponsor presents these adults to the community (see RCIA 10). During the period of their catechetical formation, they all choose godparents (a godfather, a godmother, or both) approved by the priest. Their godparents work with these adults as the representatives of the community and have the same responsibilities as the godparents have toward catechumens (see RCIA 11). The same persons who were the godparents at the baptism of these adults may be chosen as godparents at this time, provided they are truly capable of carrying out the responsibilities of godparents.
The assumption here is that if a person was baptized in a non-Catholic community, this option might not be in place.