Yes, they do tend to live in groups.
22lr to the head through the trap, wait for it to die, then bury it in your backyard. Reset the trap. If you catch another, then repeat. If you dont, then get off your butt and seal up the openings to your deck.
As an alternative to shooting it yourself, you can call animal control, who will most likely just kill it for you and then remove it.
I also posted another alternative months ago, which was to find the opening they're using and turning it into a trap door, so they can leave the porch but not get back in. That way if there is a family in there, the adults get stuck outside while foraging and sit there crying for the babies until they eventually come out and the whole family leaves to go live under your neighbors deck instead.
Also, dont get your fingers, dog, child, etc near that trap, some individuals will just cower, but others will suddenly attack.