It can be a challenge, especially when the female is unable to work while taking care of the baby.
When my little people start asking me for things I tell them
they'd better start working hard and saving up! LOL! No watching tv or playing video games, just work, work, work and looking for collectibles.
Also, some careers pay more than others. If you're still in the 1st generation and you want to adopt someone with a different career you can use the Evict
button in the "Settings" menu (within the game tap Menu, then Settings) to start a new family. You'll keep all the upgrades you've done to the house and keep all the money in the family bank account, you'll just lose your current family.
You will only see the "Evict" button if you're in the 1st generation. It'll be right next to the "Done" button.