We’re planning on selling our family home, but haven’t found our new house yet. Can we put our house on the market while we’re still living in it?

You can work on both at the same time! While  you start searching the internet looking for your next home, you need to get yours on the market. ( If you find the right home, and cannot purchase without selling your home, then a seller will want to know that you are actively marketing yours for sale.) If you have a lot of equity in your present home, you might check into a bridge loan and go ahead and buy a new one and then sell your home once you are out, but that is not always an option. And only if you can afford 2 house notes!  So best to search internet and do some drive bys and once your house is on market; work with your agent and start visiting houses; so that when your house is under contract you can make an offer on a new one!  Since our area still is in a buyer’s market, a seller may accept a contingency contract with a first right of refusal. That would give you a place to move to once your house is under contract.