To endanger a relationship through thougtless or insensitive behaviour. Usually used in the past tense, after the relationship has in fact ended due to said behaviour.
If I forget the missus's birthday I will really kick the dog.
I can't believe I forgot the missus's birthday. I really kicked the dog this time.
The phrase describes the process of resetting the watchdog timer of a CPU. This part of the hardware ensures that the device doesn't get stuck in an infinite loop. If the dog doesn't get kicked from time to time, the CPU resets.
John: Hey Buddy, let's kick the dog!
George: I normally don't abuse animals
John: No, I just want to reset the watchdog timer