From “The Tidings of the Resurrection”, translated by Whitley Stokes.
It is asked, now, will there be a resurrection for human abortives…? The answer to that is, that beyond there will certainly be a resurrection into life for all who have had death here after life. If, then, the abortives had death after life, even in their mother’s womb, it is certain that they will have a resurrection beyond, and that they will have life (again) after that death. If, then, there is thus no doubt of the resurrection of abortives, much less is there doubt of the resurrection of infants….
…‘All men’, quoth the apostle, ‘will arise out of death in the likeness of the age and form of Christ.’ …Whatsoever, then, is wanting of completeness in their body to abortives and to little infants… which have not their lawful size and are defective in certain corporeal members, the Lord will supply beyond in the Resurrection, so that naught shall be lacking to them of the full propriety of their form or of their proper nature. For that is a thing which they possess in themselves, according to the invisible and hidden law of their nature, though they have not possessed it according to material nor according to bodily size… as Job affirms when prophesying in his book and saying that all men will arise in their proper bodies.