A plot bunny is an idea that tends to multiply without warning, much like a pair of rabbits. The good point about plot bunnies, you will never run out of ideas for writing. The bad point, there’s not enough hours in the day or or months in the year to write out every plot bunny that comes along. Much as you would like to write up every one, I fear your well-being will suffer.
If the plot bunny continues to stare at you, you had best write down what is it. Get as much of the idea written out as possible, then go back to what you were previously working on.