Think about it - if you have a kid or kids, you just can't afford to maintain the same life style at least for a while. Things require a different approach. Being a parent is a job of its own.
As for that second sim - I had a case where my sim had to take care of 2 toddlers because their own parent could not be bothered! One of them was dirty, hungry, crying mess. It think that only sims with family traits will prioritize children over themselves. Micromanage.
As for lunch packs - my apologies, but I have no idea. In all honesty, with so many sims food will not laast long. It might be prudent to work on chef aspirations - you'll cook A LOT.