Board Thread:Help Desk/@comment-79.134.34.107-20130317063646/@comment-6909249-20130317141706

Yes, they do respawn. They may not be respawning because you don't have the requirements of a house. When you go on Terraria, click othe house icon. It is above your 'Equip' items. Once you have clicked on it, click on the question mark (?). This is a housing query. Next, click on the rooms that your NPC's were living in. The housing query will tell you what you need to add to your house.