First, let's go deeper into this "Children of Men" thing.

Regardless of what caused it (writers: hint, hint) or when it started or where it started, the path is always the same. It varies only by age and birth gender. Adults (men/women), Teens (males/females), and children (boys/girls) each have a different but consistent path they follow. Pregnancy does have an alternate path for females (women/teens). I will detail the entire path here. Starting with children (age 0-12), males and females tend to experience things more quickly than their older counterparts (adults/teens).

Children (boys and girls alike) tend to:

1. Lose their genitalia. Their genitalia will a) fall off/out, b) be absorbed by their body, or c) both. (This process may take anywhere from a few seconds to several hours depending on the authors preferences, but will always be less than 24 hours. There are rare exceptions wherein the change takes a great number of days, but this only happens when the author is having trouble making the ordinary timeline work.)
2. Lose their anus. The child will find their butt growing smooth and, likely, shrinking in towards the body to give them a flatter, smoother backside than normal. This typically takes 1-3 hours. Being active can occasionally drive the time down to less than 15 minutes, but this is rare and only really happens when there is a damn good reason.
3. Lose their face. The child will retain their ability to see and hear, but will no longer have more than a manikin-like face with only the slightest hint of facial features. This may go several different ways including a) the facial features fading away, b) the face sliding or peeling off like a sticker, or c) both. This takes 10-15 minutes at most. (The author has discretion in this choice, but should remember that it must be consistent with other aspects of the existing thread.)
4. Lose their internal organs. This is a mostly "off camera" process, but there may be some situations in which this could come up. This is a nearly instantaneous process taking a few seconds as the internal organs, much like the genitals, simply drop out of the body. Usually this occurs before the loss of the anus or genitalia, but there may be some method by which this could occur afterwards.
5. Lose the need for food and water. This is not something which comes up very often as the only way in which anyone would know is if they happen to observe the child long enough to see the kid avoid ever drinking anything. The fact that the child lacks a mouth would lead most to assume the child is incapable of consuming food and water so it would not be much of a leap to assume they don't need food and water.
6. No longer need to sleep. This does not mean that they are no longer capable of sleeping. It just means they no longer will do so automatically.

Teenagers are bit more complicated as they are old enough to make some decisions but generally not old enough to be allowed to engage in sex. Thus, while they are capable of sexual activity, they will be treated as virgins for any sort of expressed situation. Obviously, they can get up to many "naughty" things off camera, as it were. We will simply not see it or hear about it. However, it is possible to hear about their more...active bodies. What this means is that, since teenagers go through the puberty at this age, their path is just a little more involved. Also, female teens and male teens tend to diverge on their path to being completely genderless.

Female teens experience the following changes:

1. Breasts and nipples erased
   -- Breasts shrink away
   -- Nipples "fade" away
2. Lose their sex/gender
   -- Genitals are "erased"
   ---- Lose reproductive tract
3. Stop wearing bottoms
   -- No panties/underwear
   -- No pants/skirts
   -- No bikini bottoms/swimsuits

Human males of adult age experience the following:

1. Lose their sex/gender
   -- balls shrink or fall off
   -- penis is absorbed or falls off
2. Stop wearing bottoms
   -- No underwear/undershirts
   -- No pants/shorts
   -- No swimsuits

Humans of adult age experience the following changes:

1. [See humans above]
2. [See humans females or males above]
3. Lose interest in sex and sexual activity
4. Become incapable of bladder and bowel control
5. Spread the changes to as many people as possible.
6. Actively hinder efforts to combat the changes

Humans of adult age are affected as follows

1. Stop wearing tops

When the person first enters this stage (0-6 hours), they will begin to feel uncomfortable. A feeling of itching will be felt wherever clothing is touching the upper body. Most effected individuals will, over time, make excuses to wear such items of clothing less and less. This stage is often marked by increased resistance to covering the chest region. This may be a compulsion to remove articles of clothing or simply refusal to put them on to begin with. It should be noted that those who are in this stage can be aggressive when confronted. Though, more often than not, stage 1 individuals will simply avoid the person attempting to the issue. It is recommended that anyone who is or knows someone who is in stage 1 get immediate medical help as it is only at stage 1 that the effects can be reversed. This advice, sadly, will likely fall on deaf ears as most in stage 1 fail to recognize that they are, in fact, in stage 1.

The best advice is do not the issue with a stage 1. Try your best to convince them, but do not push it. Let them decide for themselves.

Total Time in Stage 1: 0-6 hours

Human females change as follows

2.1 Breasts and nipples erased

When a female reaches stage 2a, she will begin to exhibit strange localized changes. First, most Stage 2a females will begin to lose definition in their nipples as if the nipples are being erased from a picture or video. This will occur in both in real time and in recordings of the female. However, the effect only goes back as far as the onset of adulthood. This means that any photos or videos of the person taken before they reached the age of adulthood (18/21) will be unaffected. All other recordings (video/photos/etc.) will reflect this change. As Stage 2a progresses, the subject will begin to regress in the chest area. They will, over a period of 12-24 hours, see their chests shrink down to literally nothing, including 95% loss of breast tissue. As their nipples will have long since (12 hours) been lost, the result of this shrinkage will be a featureless, genderless chest. That is not to say the person will have a masculine chest.

On the contrary, they will have an ambiguous, androgynous chest. It will be almost as if their chest is that of a child. There may even be a slight bit of child-like pudge to it. All those who have loved ones or friends who have entered Stage 2f are advised to treat the person as if they simply have an illness. Try to downplay the severity of the changes. It has been found that Stage 2 can cause severe depression. If you are unable to lift the subject's spirits, it may become necessary to hospitalize them.

Total Time in Stage 2: 24-36 hours

2.2 Lose their sex/gender

Stage 3f

2.3 Stop wearing bottoms

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Human males change as follows

2.1 Lose their sex/gender

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2.2 Stop wearing bottoms

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3. Lose interest in sex and sexual activity

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4. Lose bladder and bowel control

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5. Spread the changes to as many people as possible

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6. Actively hinder efforts to find a "cure"

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