Pretty Self expanatory

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Nrass Master Controller - This mod is more like a feature it makes it so you can edit in CAS and change game mechanics. its VERY HELPFUL and can allow for clothing to be used by both genders and well as accessories and makeup to every age. also allowing multiple makeups and accessories overlapping in the same category. Can also expand the sim household to more that 8.

Nrass Portrait Panel - Makes it so that your game can have more that 8 sims per household, also expand the number of portraits on the left side of screen.

I recommend that you download both the mods above they work in harmony with one another, Master controller allows for more than eights sims per household, and portrait panel expand the number of portraits on left side of screen in game making the more that eight sims playable.

PS. Download the newest version (Base-Mod).

There's actually a few more too it than that if using NRaas mods. MasterController only allows for Greater than Eight if you use a MasterController command to arrange such a household such as its own Add Sim, Pollinate, Instant Baby, Adopt commands.

If you want to be able to make babies in a full household the romantic way, you need Woohooer.
If you want to be able to move sims into and out of overstuffed houses using the phone/computer or Edit Town, you need Mover.
If you want inactive households to be able to overstuff themselves, you need StoryProgression.

PortraitPanel makes already overstuffed households more playable, it doesn't do anything to allow or disallow them from forming.

http://nraas.wikispaces.com/Which+Mod+FAQ#Overstuffed