Check the hose between the radiator cap and the overflow bottle. When the cooling system is full, the pressure pushes the coolant out of the rad cap into the overflow.
As the system cools down, the cooling system contracts and sucks coolant into the block (system). If there is a hole in the hose between the two, or it has fallen off, or the bottle has a hole or crack in it, the coolant ends up on the ground. The engine will run fine while its warmed up. When you shut it off and it cools down, it draws air, instead of coolant, back into the block. Next time you start it up-----not enough coolant, and you overheat, plus you get to re-burp the engine and heater core.