You can't make them eat and you can't make them sleep. My dd slept through the night for the first time at 16 months.
The only thing you can do is rearrange your life a bit until you find something that works for you. Two family beds, a family bed and a crib, a family bed and a bed for your 3 year old. A family bed with a crib side-cared to it.
This won't last forever, I promise! One of the things I have had to teach my dd7 over the years is that even if she wakes up, she needs to stay in bed at night. I will always come to her if she needs me but to save her questions or chatting for morning. She is still up throughout the night but does not disturb the rest of the house, even though she would really like to. LOL!
