How to bring the husband back to life (actual solution)

- Kid learns how to lucid dream.
- Kid chooses to dream about a time machine.
- Time machine appears in Kate Bosworth's house.
- Kate uses the time machine to go back to before the husband died.
- Puts husband in the time machine and takes him back to the future.
- Kid wakes up.

Could also use this method to bring the others back to life too if they wanted to.

Also, since they already established that things affected by his dream manifestations remain in effect (ex. the butterfly bit her, so even after the dream ended she still had a bite on her hand) you could do a lot of cool things with that. For example the kid could dream about a vampire, have the vampire turn Kate into a vampire, and now when he wakes up he's created a real life vampire species and he can make himself live forever.

Or he could dream about a cancer curing serum, then it will appear in real life, the person with cancer takes it and is healed, and remains healed after he wakes up. Lots of interesting things to try.