It’s quite possible that those Saints stayed on earth, spreading the news about Jesus to others, perhaps especially to members of their own families, until He ascended. Like John says, " 21: [25] But there are also many other things which Jesus did; which, if they were written every one, the world itself, I think, would not be able to contain the books that should be written." There are also many other things that occurred during those early days of the Church that were not all written down, either. Those are some of the things that were only passed on orally, through the Sacred Tradition of the early Church.