Masturbation means the production of an orgasm (climax) by the manual or mechanical friction of the genitals. This, I might add, has been going on for a long time, for it comes from the Latin word masturbatie, which has the same meaning as it does today. Now small children have no knowledge of sex, and until after puberty at least, orgasming, in the true sense, is simply not possible, for sexual development is an essential prerequisite.
Children, from babyhood on, are learning. This they do via all the senses, and this includes touch. With their two hands and ten fingers they will avidly explore every part of their body. This is part of juvenile education. It’s all a matter of learning. So crevices, cracks, knobs and appendages all come within this orbit.
In babyhood and childhood, definitely no. They have never heard of sex and so know nothing about the sex act or sexual relationships that are such an important part of life as one develops and matures. What about sensations?
They may gain some gratification from “playing with himself/herself’ (as some parents explain in horror). But they may also gain delight from tickling their feet, hands or stomach. This is all, and any gratification is within any normal physical and mental bounds.
I believe they should ignore it. Some are bowed down by guilt feelings, probably from a strong religious training, or the thought that anything in this area can only be wicked, sinful, the work of the devil and so on. This of course is incorrect. Ignore the whole activity and soon the child will do likewise, and it will be of little consequence. Do not blow it up out of proportion, for it is not important at this stage of life.
The less attention that is given to this passing juvenile habit, the better. Do not remonstrate, scold or abuse. Rather, ignore it. Probably try to get the child interested in other entertainments. These may be varied and there is no shortage of material to which to turn.
As children become older they will naturally ask questions. Answer them with frank, straightforward, honest answers. If you do not know, tell them so, but start to educate yourself and find the answers, for they will keep on coming, and they will gradually become more and more complex, believe me. I have been doctoring for many years (and have been a father for many years also, and know the type and range of queries that are fired at parents).
Do not appear embarrassed. If you are not, they will not develop this attitude either. Do not adopt an attitude of guilt or shame. This is anathema and can immediately put up unwanted barriers.