Canon LXXII.
Canons of Local Councils Received in Trullo (Sardica, Carthage) · The Seven Holy Ecumenical Councils
Item, it seemed good that whenever there were not found reliable witnesses who could testify that without any doubt they were baptized and when the children themselves were not, on account of their tender age, able to answer concerning the giving of the sacraments to them, all such children should be baptized without scruple, lest a hesitation should deprive them of the cleansing of the sacraments. This was urged by the Moorish Legates, our brethren, since they redeem many such from the barbarians.
LocalT 2.76.3
It seemed good that they should be baptized about whom there was an ambiguity whether they had been baptized or no; lest they might through that doubt lose the divine ablution.
LocalT 2.76.6