A spouse or future spouse can enter the household at any time (even born in household), but if not born there, must be brought in by the heir. Spouses, except spouses 4, 8, and 12 (future founders), and spares, and really anyone except heirs and founders, can have any career, any rewards, any opportunities without restrictions. So go ahead and have them get those chef's fridges, if you want.
Edit-beat me to it, Nutella.