Turn its volume down, high pass filter, and reduce the decay/sustain. Bit of eq to make it a bit different. I'd tune mine by cents, as a semitone starts to sound melodic up/down/up/down to me. You might also try adding a touch of distortion to the main snare, but not the ghost. If you've reverb on the main snare, turn it down too for the ghosts. Increase its attack sdightly to dull the initial transient. Anything and everything to make it feel like a softer, gentler version.
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Also, possibly tuning the ghosts lower. I'm not entirely certain now, but I think the skin of the head gets stretched and vibrates faster on harder hits.. anyone know?