Looking for a way to get the family praying together without it feeling like a chore to get EVERYONE involved?!?! Start a Family Prayer Tree.
Order one those tree bulletin board sets, here is a favorite of mine:
Take a wall in the house that everyone passes by, put the tree up without leaves. Use a ziplok baggie to hold the leaves or make a pocket to put on the wall nearby to hold the leaves. Have each person take a leaf and a marker to write on the leaf a prayer request of theirs and date it (if a wee one, have them draw a picture and help them date it) and then hang on the tree. Then pray over each request together. When you come back together as a family, review the leaves already up on the tree and take them off the tree and stick them around the bottom like a fall tree scene that shows God answered it and write the date God answered it.
This will be a living visual of how God WORKS in your lives and cares about everyone's request no matter how simple, how complex, how weird, how strange, how impossible...