If she had her babies there she will most likely come back. Not only will she come back but the offspring in many cases will come back where their mother nested to have their young. You need to be vigilant during the two times a year they nest to have babies. If you notice they get access again you need to trap them immediately and relocate them at least 10 miles away. The only way to rid them is a trap, preferably an exit trap. They are very persistent and will not give up. I had a neighbor battle them in his attic and he finally called in a pro who set exit traps and relocated them. Sprays may work but I would worry about the smell. A firearm would work too. A stakeout and a .22 would rid them quickly.