If you were to look at things anthropologically you would find that most village shaman/healers, etc. were set aside when quite young based on a series of "markers' that would be noted; gender association typically topped the list in that sexual identity tends to first reveal itself sometime between 3 and 6 years of age, something that human behaviorists have been confirming more and more since the 1970s. The other things they look at are situations such as the child having conversations with the unseen. While modern researchers chalk this up to "Imaginary Friends" they are only partly correct in that assumption; where much of it short-termed imagination there is a secondary relevance in which this friend becomes a near constant companion for years at a time.
Then we come to Past-Life scenarios; when a toddler insists that his/her name is ___ and not what their birth certificate indicates. Not only that, but they can give you some strange item-specific details about that entity, where & when they lived, what was happening during that time and if they were confronted with items from that past or actually being in the place they associate with, the memories will intensify with details and recollection such as you find with the Buddhist traditions around the great teachers such as His Holiness the Dahlia Lama. On the other side of this coin, you will have such children "recognizing" people from these past life-times and being able to convey "facts" about these total strangers then and now.
The "Invisible" elements are a biggie in one other way; when family, family friends as well as community elders would see ancestors tied to such children, given them care and protection. In other words, a grandparent or even sibling that has passed over and yet they remain with this progeny as a kind of spiritual support team. Such things are almost always reported alongside seeing these children "glow" -- a unique radiance around the child especially when it is exceptionally happy, espousing certain information in a serious manner or, in the instance of natural healers, when in the process of healing something, which frequently includes gardening and helping plants (they always talk with plants).
I've got long memories of such things myself which is one reason why I started long ago, trying to understand why I was "different". The sad truth being that our Judeo-Christian culture simply adopted blinders and looked at these things in a negative light (proof the child was possessed) rather than nurturing such children and helping them grow to be the type of person they were born to be. In my case the acts of oppression ranged from beatings to lots of "laying on of hands" and having this and that preacher to group paying over me. . . after a bit over a year of it (I think it was) I simply learned to suppress things and not talk about them which was fine until puberty kicked in and said "things" started bombarding me again, this time in a very intense manner. They were accompanied by a reunion of sorts, with my childhood chum -- that imaginary friend I had from the time I was roughly 3 1/2 well into my 6th and 7th year.
Everyone will have one or two of these things happen around them in that everyone is born with some level of "sensitivity" and when it comes to spiritual factors, we all have ancestors that will nurture & protect us when we are young, this is something that most all world cultures share when it comes to general belief.
When it comes to "Psychic Development" I simply believe that 90% of what's being put out there is pure tripe; an amalgamation of western & (mostly) eastern occultism that's been commercialized over the past few centuries, most notably since the latter 1800s with two huge spikes in the late 1960s/early 70s followed by the 1980's resurgence (when those that were young during the hippie era, wanted to recapture what they thought things were previously. . . just without all the narcotics this time around; the focus was more on health, alternative healing and looking pretty. . . becoming "wealthy") . While having someone to guide you when you are ready to remember your psychic side is almost necessary, finding a guru that expects obedience and servitude is not. Any genuine teacher GIVES and does so freely; they are compelled to serve the Universe and no their own pocket-books, egos and dreams. That is not saying that some form of exchange doesn't happen, it must! You can't get something from nothing, but when it comes to this kind of thing the exchange is rarely a thing of currency or barter. But as I've intimated, such teacher-student connections are rare and frequently mean that the student will end up meeting many teachers over many years, learning what they can from each for the time they are together. In my experience the "teachers" I've known have rarely been some ego sitting on a pink pillow and telling me to chant; most were crusty old salts that simply understood life, nature and people; they spoke in unflattering ways (according to the pretty ones) about the beauty and wonder within life and how "man" loves to ruin it all.
I acknowledge only a handful of formal "commercial" personalities as mentors in my life; Louise Hay and to a far lesser degree Marianne Williamson are two of the better known followed by Bro. Anthony Penera () and Joseph B. Wilson (T.O.T.E.G.) my real teachers however, came about as I needed to "hear" their voice --
when the student is ready, the teacher will come -- not all such teachers are physical or even human, it's amazing how much you can learn form a dog or cat when it comes to unconditional love that really is "unconditional" -- how you can gain a better comprehension on Reincarnation by reading about a Seagull named Jonathan or true metaphysical thinking by flying about the country in bi-plans as was done when reading the book ILLUSIONS by the same author.
It's no easy journey in our current age but the Piscean influence is in the wane as Aquarius shifts into power. . . unfortunately, it's going to be at least another century before we really see the effects of such things and too, there's going to be a bit of hell to pass through prior to finding "heaven" -- a restoration of mankind actually finding "the divine" in ALL facets of in life -- in ALL things. Funny, how nearly loosing it all tends to be the only thing that wakes us up, isn't it?
Anywho... my thought train has derailed somehow so I'll leave things here for the moment.