Okay so I don't know if this is just coincidence or a possible indication of there being something corrupted..but there is an abundance of baby girls in my neighbourhood. I thought it was just pure chance, but playing for the past hour, two more baby girls have been born!

My neighbourhood is called Riverside (not the downloadable one), and I've been playing it for a few months now. I really can't remember when I started it, but I want to say at least September I know I had it, so a fair few months. In that time there have been many pregnancies, but no baby boys at all! I've just checked and here are the ''birth records'':

Baxwell: Georgine, Amber, Melissa
Jennison: Savanna, Madison, Britney
Effa: Eveline
Courtenay: Sasha
Aege: Katherine
Perrot: Monica
Shaw: Marie

That is ELEVEN girls! This is weird, right?! I do have a teen boy and a child boy in the neighbourhood, but they were made in CAS, not born in game.

I mean I know it could be just a really big coincidence. But with eleven pregnancies and a 50/50 chance of a boy, you'd have thought at least one would've been born by now! It's creating a very noticeable demographic in the neighbourhood!

No, it's not. This is fine. It's called a statistical cluster and it is the only math I will ever be able to explain to you, so listen up.

Since Sims2 uses a simple binary gender system, it determines sex at birth with a "coin flip" randomization - i.e. two choices, with an equal chance of getting each. That's clear, right?

Over enough time and given enough chances, therefore, we can expect that about half the sims born will be boys and half girls, right?

Not exactly. The expectation is reasonable - but only in the aggregate, over time. The odds of rolling a boy next time do not go up a little every time a girl is born. The odds are exactly the same, every single time. You will always have an equal chance of getting a boy or a girl. Always.

You see how that works? You can get absurdly long strings of one sex or the other in the normal, blind operation of probability. It happens to most of us at one time or another. I'm currently playing an Uberhood Challenge with Widespot attached, and so far all four Widespot babies, every Challenge baby, and every incidental baby born while playing other households to synch ages, has been a boy. For awhile in Drama Acres I had a run on girls so strong I called it The Generation of Lesbians and added a huge household of boys as they came of age.

You have a couple of recourses. One, make some boys of your own - add a new family, brew up some CAS townies, add a University when this crop of girls hits that age and marry them to dormies and premades.

Two, to save shortly before the birth, and when you don't get the sex you want, quit without saving and try again. And again. And again. For however long it takes to break the statistical cluster and get the desired result.

Three, to roll with it and develop in-story responses to the Girl Glut. Normalize female/female marriage. Privilege adoption. Invent female/female reproductive technology. Enable female alien pregnancy. Whatever suits the hood.

First of all, thank you for the helpful explanation! I get the maths/statistics side of it, it makes sense. I guess I was just concerned because it seemed so much of a weird chance that when it is 50/50 each time, it always came out as a girl. Like if I flipped a coin 11 times, I would be surprised if they were all heads! Out of all the neighbourhood, two of my sims gave birth in the past hour . One of my sims is pregnant, but no-one else in the neighbourhood is planning to get pregnant for a while..so I suppose in three sim days time I can update on the gender of Riverside Baby #12.

tbh - not really. It's just a cluster.

Edit: I see Peni got there first.

One of my sim families had 7 or 8 boys before they had a girl (or opposite, I can't quite remember), but I generally get a mix of boys and girls in my game. It was probably very screwed-up chance.

The only thing I have noticed is that my game likes to even out girls and boys. If there's an abundance of boys/girls, the next babies born in that family will in most cases be the opposite gender. Also goes with twins, in that the family nearly always will get two of the opposite gender, or one of each if the genders are evened out. I've also had same-gendered triplets and quads this way. When I've had same-gendered parents, they very often get opposite-gendered babies first, and then follow the previous rule. It's been like this for quite a while now, but it's probably another hit from screwed-up chance. Still, it nearly always works with my test families, and they've had more babies than I can count...

Another thing is that if you play around with mods and let only one sim be the parent, the baby will always be an opposite-gender clone of the parent.

Were at least some of those girls born all in the same play session? Have you been taking steps to prevent the "first born effect"? Every time you load the game, you need to go in CAS and hit the randomize baby button several times to get the randomizer to work, or else all the children born to a couple may be identical in some way: personality, appearance, and/or gender. Or if you have the Batbox you can do Fix > Rerandomize Sim Generator.

Thanks for all the responses ..I just wanted to check nothing was wrong and that it wasn't a sign of corruption or anything. But thanks for the help - the more you know, always better to be on the safe side, etc etc

As far as I know, the Firstborn effect does not affect gender. I know before I learned about the Firstborn effect I got different genders (but identical genetics).

As far as I can remember only two sets of two were. Like I said in the past hour that I was playing, two sims had girls. I seem to recall that Sasha Courtenay and Marie Shaw were born in the same play session (but again, different households). As for all the others, they were not born in the same play session. It's not first born syndrome. For one thing, it's just gender and not looks in cases where there are siblings. And it is spread across unrelated households too.

Have you tried saving just before the birth, and exiting without saving if the baby is another girl, and then reloading? The gender is determined at birth (as well as the genetics which is why rerandomizing the sim generator during the pregnancy works), so if you do that a few times you should get a boy eventually.

I haven't, just because I usually like playing 'naturally'. I know I could probably have got a baby boy that way, but if it's a girl the first time then I like it to stay that way.

Riverside is a modern neighbourhood, so nothing like that going on there! All the families are happy with their baby girls

Last week I had a male sim who was abducted, I saved just before he set his book down to give birth. I have default alien eyes in game and the baby had the regular black ones. I decided to exit without saving and see if the eyes would change. Not only did the eyes change, the gender and facial features did too. It won't always change the gender, but the chances are better if you have the patience to repeat the exit until desired gender. Not sure what the baby will look like at aging up, considering most babies look alike and you can't tell if they will have more alien features than the parent's. I do know that some of the babies had a tiny nose, and some appeared more normal, eye size ranged from big, more normal, to small, also the eye color varied from the normal black, to my default and once was similar to the dad. The personality sign and points changed each time too. I took pictures to compare the different features but my game does not save all of them, if I'm lucky I get 1 or 2 screenshots per play. I did this 11 times, more out of curiosity to see if the changes would randomly change. Only 3 attempts created a girl.

Could be an idea to trigger a boy birth, so that you know it's possible. Perhaps you can try it for a test family in a test hood.

I've noticed that some things just won't happen at all for a very long time in some people's games, but when it finally happens it often continues to happen on a random basis. I had a very long time without natural twins (no mod, cheat or cheesecake) in my game, but after that first time it happened more often, even if it wasn't entirely common.

As Simmer23 said, it might be worth trying out just to see if you can get a boy. You can always do it again until you have a girl again if it matters that much to you. Or do it with a test family you don't actually plan to play.

Edit: DON'T delete the test family afterwards if you value the neighbourhood.

Sims that were born as twins carry a token that makes it so that they are more likely to have twins. Just like in real life, there's a gene for twin-ness. So once you have twins once it's more likely to happen again, provided you continue that family's line.

Some of the Maxis premades seem to have the special pregnancy token as well, I have seen it on a few of the Uni premades but I don't know if they are there on the same premades on all games or if they are randomly assigned.

It's always when you need the other gender. I had a medieval family that had four sets of twins and one of triplets, all girls, before they got a boy. It's one thing to have them spread around a neighborhood, it's a whole 'nother thing when you really, really, need a male heir for your peasant farmers.

I've had several lengthy same-sex strings, sometimes a glut of girls, other times boys, and I reckon them a pain because I like to keep the gender balance roughly equal. I'd rather have excess girls because they can at least have and rear kids whilst living alone and thus continue the family line. Elven girls in a row does seem rather excessive, though. But Peni explained the maths perfectly clearly, and with so many people playing the game, there's bound to be a player who gets eleven or more same-sex babies in a row. The odds are, I think, about 1 in 2000. You are the one - congratulations

Hello,

I have the same problem.
Actually in the last generation there were nearly only boys born and now there are mostly girls.
Just bad that my grown up men have no one to marry, especially the Royalty who are not successors
(I play a monarchy system in my neighbourhood)

Firstborn effect doesn't affect babies born in the same session. It only effects the first born in the session (hence the name). The 'randomiser' BTW (the code) doesn't work ever - pressing the randomise baby button just pushes the randomiser sequence along so it starts in a different place. If you always pressed it twice, you'd still have first born syndrome because it would be starting in the same place - except, I guess, in that situation it'd be third born syndrome.

Others are right though, gender is irrelevent here - that gets rolled just before the birth and is always 50-50 random.