My son started using the potty when he was about 18 months old, and I also have been occasionally babysitting 3-year-olds who still use diapers.
At the risk of inviting much displeasure (and knowing that my experience is unusual in our culture) I have to say that it seems that kids potty-learn much later these days then they used to. A day care provider I know who's been doing for 20 years says that kids start using the potty a year or two later than they did even 10 years ago--she blames disposable diapers and especially pull-ups, because they are so absorbent the kid can't really feel the 'outcome' of what they just did. Another problem is the day care environment--providers just aren't, in most cases, going to work on potty training because diapers are a lot easier that dealing with 'accidents'--and then when mom and dad come home from work, they are ALSO too tired to deal with accidents--so the diapers stay on.
A HUGE light went on when I understood the principles of EC, which I did use with my son to help him get out of diapers. (I didn't read about it in time to do it earlier.) The big one is that we *teach* kids to pee and poop in diapers--it's not just a natural thing that happens with all kids everywhere. There are millions of people in the world who do not use diapers--huge parts of India and China are an example. There kids learn to pee or poop in the appropriate spot from a very young age; baby clothes are often like long open shirts so they can just be lifted up--kids are naked underneath. The idea that kids muscles or whatever are not physicially capable of holding it before age 2 or so is just a myth, one that we value very much in our society. In societies without diapers, you learn one way of going from the time you are a baby--you don't have to suddenly make this huge conceptual leap from peeing/pooping wherever you happen to be standing or sitting (which is how it works with diapers) to going in the 'right' place in the house.
So--the reason potty training can be so hard is that we have to teach kids to poop and pee in a TOTALLY different way than we have been teaching them to go until that time. It's just a weird thing to do--like if we taught kids to eat at the table sitting down until suddenly, at age 2 we started telling them that really you are supposed to eat standing up outside. Kids who just seem to suddenly 'get it' have LEARNED to do it by watching other people--there isn't anything in a child's brain that suddenly says "Use the toilet" at a particular stage of development. (After all, no one had flush toilets until around 1900.)
I think most kids really do have to be taught to use the toilet, and yeah, I do think that a big reason so many kids train so late these days in the U.S. is because of this idea that they will do it when they're "ready" and because parents don't push it. This idea is very popular in AP circles partly because there WAS a horrible time in the U.S. when kids were expected to poop on a strict schedule (I have read baby care books from the 1940s that say to TIE THE CHILD TO THE POTTY AND LEAVE THEM THERE at specific hours of the day!!) and obviously that's not what I'm talking about.
But I personally think we have gone too far in the other direction and because of our fear of making our kids neurotic, have instead 3 and 4-year-olds who still poop in their pants--something that would be unheard of in many parts of the world. (and unheard of in 'tribal' societies like those APers like to emulate...)
Using a toilet is unnatural in many ways. (When they were first introduced, plenty of people thought it was very bizarre and unsanitary to poop inside your house.) Sitting down to poop is not the way people do it when they don't have toilets. The kid who goes outside to poop, who squats down on the ground, is behaving in a really natural, organic way!!
I don't know what the answer is, but I think that yes, there is something weird about a 3-year-old who still poops in his or her pants. But I don't think it is the fault of the individual parent (I think few parents of non-trained 3-year olds are happy about it)--I think it is a cultural thing we have going right now. So much of infant-rearing is based in culture, not biology--everything from sleeping arrangements to BF rates to how many people take care of the child. (For instance, I bet potty learning is a lot easier in an environment where more than one adult is primarily responsible for the kids). How kids learn to poop and pee is just a part of this.
At the risk of inviting much displeasure (and knowing that my experience is unusual in our culture) I have to say that it seems that kids potty-learn much later these days then they used to. A day care provider I know who's been doing for 20 years says that kids start using the potty a year or two later than they did even 10 years ago--she blames disposable diapers and especially pull-ups, because they are so absorbent the kid can't really feel the 'outcome' of what they just did. Another problem is the day care environment--providers just aren't, in most cases, going to work on potty training because diapers are a lot easier that dealing with 'accidents'--and then when mom and dad come home from work, they are ALSO too tired to deal with accidents--so the diapers stay on.
A HUGE light went on when I understood the principles of EC, which I did use with my son to help him get out of diapers. (I didn't read about it in time to do it earlier.) The big one is that we *teach* kids to pee and poop in diapers--it's not just a natural thing that happens with all kids everywhere. There are millions of people in the world who do not use diapers--huge parts of India and China are an example. There kids learn to pee or poop in the appropriate spot from a very young age; baby clothes are often like long open shirts so they can just be lifted up--kids are naked underneath. The idea that kids muscles or whatever are not physicially capable of holding it before age 2 or so is just a myth, one that we value very much in our society. In societies without diapers, you learn one way of going from the time you are a baby--you don't have to suddenly make this huge conceptual leap from peeing/pooping wherever you happen to be standing or sitting (which is how it works with diapers) to going in the 'right' place in the house.
So--the reason potty training can be so hard is that we have to teach kids to poop and pee in a TOTALLY different way than we have been teaching them to go until that time. It's just a weird thing to do--like if we taught kids to eat at the table sitting down until suddenly, at age 2 we started telling them that really you are supposed to eat standing up outside. Kids who just seem to suddenly 'get it' have LEARNED to do it by watching other people--there isn't anything in a child's brain that suddenly says "Use the toilet" at a particular stage of development. (After all, no one had flush toilets until around 1900.)
I think most kids really do have to be taught to use the toilet, and yeah, I do think that a big reason so many kids train so late these days in the U.S. is because of this idea that they will do it when they're "ready" and because parents don't push it. This idea is very popular in AP circles partly because there WAS a horrible time in the U.S. when kids were expected to poop on a strict schedule (I have read baby care books from the 1940s that say to TIE THE CHILD TO THE POTTY AND LEAVE THEM THERE at specific hours of the day!!) and obviously that's not what I'm talking about.
But I personally think we have gone too far in the other direction and because of our fear of making our kids neurotic, have instead 3 and 4-year-olds who still poop in their pants--something that would be unheard of in many parts of the world. (and unheard of in 'tribal' societies like those APers like to emulate...)
Using a toilet is unnatural in many ways. (When they were first introduced, plenty of people thought it was very bizarre and unsanitary to poop inside your house.) Sitting down to poop is not the way people do it when they don't have toilets. The kid who goes outside to poop, who squats down on the ground, is behaving in a really natural, organic way!!
I don't know what the answer is, but I think that yes, there is something weird about a 3-year-old who still poops in his or her pants. But I don't think it is the fault of the individual parent (I think few parents of non-trained 3-year olds are happy about it)--I think it is a cultural thing we have going right now. So much of infant-rearing is based in culture, not biology--everything from sleeping arrangements to BF rates to how many people take care of the child. (For instance, I bet potty learning is a lot easier in an environment where more than one adult is primarily responsible for the kids). How kids learn to poop and pee is just a part of this.











Well except for the really foul poos...
: This reminds me so much of how Joe was. He was 3 years nine months- no, I think he weaned at 3.9, & potty learned at 4.5. Yep, that's right. (How funny that I had to think about it, when he was that age & people were implying he would never be out of pullups, I thought I would never forget the date of such a "milestone!") Anyway, Joe had a phobia of pooping on the potty- he would go in the playroom, alone, lean on the bed, & poop in his pullup. So I knew he could tell when he had to go, & I also knew that when he was ready, he would move to the toilet- & he did! 
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