Into the Night
Verified User
Obviously, Kirchoff's law preserves Stefan B and allows the 2nd of law of thermodynamics to not be broken.
In an isolated system, the exchange of heat between two radiant heat sources will eventually result in a temperature equilibrium between the two. Thus the 2nd law of Therm is preserved.
However, there is no 'net heat'. Heat only flows from hot to cold. A colder object is not a heat source.