First you need to put the family in the family bin after that you can move them in any house in that neighborhood,but you can't move them in other town(neighborhood).
Yes you can get other sims to move in with your sims.Also if you want to know how to get sims to move in with each other:If you want to get them to move in with your sims then try becoming Best friends with that sim and then have a little look in the "Friendly" option when you are talking to them, the option "Ask to move in" should be there.hope this helps :)
on the edit town mode you can merge households. also if your sim is good enough friends with another sim in another household and they are at that sims house at the moment then that other sim can ask you if you would like to move in
Once you move one sim to an island (except for crystal island but you haven't unlocked this island yet) the other sim will just be there lk if you make a fire and declare home they will be there by nite fall
your other sims that you made have to be in a high relationship with the "ready-made sims" (NPC's) They have to be at least best friends or something like that, click on them and click on "propose..." then click on "move in" they will hug your sim if they have accsepted. Either that or you can click "propose..." then "engagement" then after your sim marries them, they will move into your sims house.
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Either buy one or make on and just move your sims into a lot to make one or move your sims into a house its that simple-hope you have fun
If you move them into a new house they are playable.
try moving to a new house and move everyone into the new house
First of all you have to have good manners to your sim the you can become best friend the you ask the other sim to move in then we are all set up ENJOY! ;)
There is a cheat but I don't know it. Basically you have to make your sims fall in love (get their life-time relationship above 60) and then you can 'Propose' 'Move In'. The other sim may say no, if they do, you have to get their life-time relationship up even higher and try again. Or you can go to the neighbourhood and move a sim from the family bin into the same house as another sim.
go into edit town mode and click on the sims you want to add and click place copy. then click on the house which your current sims are living in and say yes when it asks you if you want to merge the two households hope this helps :D
Build a friendship between the two sims & then eventually it should have "Propose.." "Move In" in that pie bar when you click on another sim.