It can happen by chance or you can use a cheat: SHIFT+CONTROL+C, then type forcetwins. My sims used the cheat once, then the second time they still had twins so be careful, because the guy can have a gene thing, that makes him have twins.
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How can I have boy girl twins on the sims 3 pets ps3
on sims 3 have the fertility treatment on both the sims and then while they are showing make them listen to kids music or you will end up with twins if you do it wrong on sims 2 you will have to get a hack
No u can't
To get twins, you can use the cheat "forcetwins" in the cheat console after your sim is pregnant.
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