Do you mean having all of them at once with you? You cannot. you can only have one other with you along with also having ED-E.
dam I have two staying at home and wanted to get rex.
You need to use this mod, Unlimited Companions www.newvegasnexus.com/downloads/file.php?id=34870
By default you're only allowed to have 1 Humanoid and 1 Android Companion, if you apply the mod you can have as many Companions as you like. Vanilla as well as modded (ones you add to the game) Companions.
The mod works really great I have all the vanilla companions with me, my own personal little army :P
Or you can just add them through the command line.
You need to use this mod, Unlimited Companions www.newvegasnexus.com/downloads/file.php?id=34870
By default you're only allowed to have 1 Humanoid and 1 Android Companion, if you apply the mod you can have as many Companions as you like. Vanilla as well as modded (ones you add to the game) Companions.
The mod works really great I have all the vanilla companions with me, my own personal little army :P
Or you can just add them through the command line.
Am on a Laptop Tommy, Even my work around to get the Console up I dose not work all the time and fallout 3 n fallout NV are two it dosent seem to work with.
And Cabola thanks for that I tryed to find somthing like that I must have missed it.