To me it's so important that none of the Grunts realise that Lyla's actually dead.
I feel a lot of people overlook it but it adds to the misery that is their household.
Like all three of her sons are hoping she'll come back for them...
Tank is hoping she comes back so he can be himself because he remembers how soft she used to be with him and he's idolised his mother to this near perfect human being. To Tank she's something she never was.
Ripp is hoping she comes back so he can stop fighting. He doesn't want to argue with his dad but knows if he doesn't put up a fight against Buzz's expectations no one else will. Ripp believes his mother will fight for them so he can just be a teenager again.
Buck is hoping he can get to know her. She left when he was so young he barely remembers her and wants her in his life. He remembers her as the only parent that cared for him.
Tragically none of them will get what they want, the only one who does is Buzz.
And Buzz is terrified Lyla will come back for their sons. He's spend the better part of a decade trying to mould his sons and control them. He might not like Tank, but Tank has met some of his expectations, Tank's desperation for Buzz's approval will have him joining the military in the blink of eye if it means Buzz will be happy. And Lyla could come back a ruin it all, for all he knows Lyla's spent years getting her shit together so she can win custody of them when she couldn't initially.
But because she's dead she never will, so Buzz can keep being Buzz. Buzz can keep torturing his sons physically and mentally because they just need to "toughen up." And the boys just have keep dealing with it until they're old enough to get out of there (but if the Sims 2 for PSP is to be believed, they never will).
