Can. 892 Insofar as possible, there is to be a sponsor for the person to be confirmed; the sponsor is to take care that the confirmed person behaves as a true witness of Christ and faithfully fulfills the obligations inherent in this sacrament.
Can. 893 §1. To perform the function of sponsor, a person must fulfill the conditions mentioned in can. 874.
2. It is desirable to choose as sponsor the one who undertook the same function in baptism.
The Catholic Church requires sponsors to be Catholic, baptised and confirmed, practising the Catholic faith, and at least 16 years of age. (Code of Canon Law, Can. 874 §1)