Grahame Fallon (November AD2000) quotes Pope John Paul's words that aborted babies are now "living in the Lord". But that expression should not be taken as a denial of limbo, for souls in limbo have great natural happiness and a knowledge and love of God.
It is widely asserted today that unbaptised babies go to heaven, but this view is not supported by Tradition, the teachings of the Church's magisterium, or that of the vast majority of theologians through the ages. The solid teaching of the great Fathers, doctors and theologians from the early centuries onwards is that, apart possibly from exceptional cases, unbaptised babies do not go to heaven.
This is supported by the Second General Council of Lyons in 1274 and the General Council of Florence in 1439. It is the teaching of the Catechism of the Council of Trent.
In 1980 the Congregation for the Doctrine of the Faith issued an Instruction on Infant Baptism which, having reviewed the Church's teaching and practice through the ages, stated: "The Church has thus shown by her teaching and practice that she knows no other way apart from baptism for assuring children's entry into eternal happiness."
The Code of Canon Law states: "Parents are obliged to see that their children are baptised within the first few weeks" (canon 867).