There isn't a cheat so that you will just be able to have unlimited amount of sims that you can add to your household but there is a couple of things that you can do if you have 8 sims in your household and you want to have more.
Frist you have to press Ctrl + Shift + C then type in "boolprop testingcheatsenabled true" if this doesn't work the frist time go back and make sure you are doing it right and putting the spacing in the right spots.
When you are done with that Shift + Click on your selected sim then go to Spawn, find Tombstome of L and D and select that.
A tombstone will apear next to your sim, click on it (your sim can be anywhere in the household and it will still come up with its options)
Then there will be options such as "new boy/ girl toddler/teen/adult/elder" and somewhere it will say (may be in "more") new baby. This will be random so it may be a girl or a boy. You will not have the option to name the baby or any other age sim so you have to select the sim that you want to rename (unless it is a baby then you will have to wait until it is a toddler) and then (I believe) Shift + Click on the sim that you want to change the name for and the look through the options and it should be in there somewhere call "rename Sim" or you have to click on the "Tombstone of L and D" and look through the options for that.
If you do make a new sim like this (I tried) it will not be related to any of the sims that are already in the household but it will still have the same last name as the sims in the household.
Also for future sims playing if you want to get you sims pregnant without having to do the "Try for Baby" then you select the girl that you want to get pregnant and click on the Tombstome of L and D and find "Get me pregnant with..." and then choose the sim that you want the girl to get pregnant with. (This does work with girl but I don't know if it does with guy and guy) Also if you want to get one of your sims pregnant with an alien baby, select that sim, click on the "Tombstone of L and D" and find "Get me alien pregnant"
There is also a lot of other thing that you can play around with the "boolprop" cheat and the "Tombstone of L and D"
I hope that this helped and you have fun playing around with the options with the cheat!
if you bring up the life or death tombstone you can
You can have up to 8 sims per household however if you have 7 sims and 1 of them is pregnant with twins or triplets you can have more.
Nope, you can only have 8 people in a household at one time. If you want your sims to have more children, you're probably going to have to move some people out.
Up to 8 people, or, if you have Pets, a combination of 10 with no more than 8 sims or 6 pets.
none, sorry (it's completely impossible) :[ You can only have four Sims in a household. So you can only have twins.
Well you can have up to 8 people in your household.:)
if you bring up the life or death tombstone you can
there is no cheat but there is a lifetime wish for it
In Sims 3, if they are in your household, then yes you can. If they're not, you still can with the help of a cheat. When 'testingcheatsenabled true' is on, you can shift click another Sim and select 'Add to Active Household' and they will be added to your household and you can act them. This cheat only works if your household is NOT full.
You can have up to 8 sims per household however if you have 7 sims and 1 of them is pregnant with twins or triplets you can have more.
Nope, you can only have 8 people in a household at one time. If you want your sims to have more children, you're probably going to have to move some people out.
IntProp maxNumOfVisitingSims 8
Up to 8 people, or, if you have Pets, a combination of 10 with no more than 8 sims or 6 pets.
no the biggest number of people you can have is 10 i think
8In a single game (one household), you may have up to eight sims. However, you can have as many games as you like.Then explain why i have 13 people in 1 householdMmkk1122: It is not possible to have that many people in the Sims 3... are you sure that this is not relationships eg: Girlfriends/ boyfriends etc, not sims that you have control over?
no
none, sorry (it's completely impossible) :[ You can only have four Sims in a household. So you can only have twins.