This plant is Arum italicum. It is highly invasive in other states. It is also toxic to humans and pets. 

Here is a profile from North Carolina State University with lots of photos and additional information. 

If you are able to remove it, I would encourage you to do so. If you choose to remove it, be very careful. First, remove it before the seeds (they're turning red in your photos) fall off. You might want to cut off the seed heads and put them in a plastic grocery bag, tie it closed, and put it in the trash. Then, gently dig out the tubers. Any tubers, no matter how small, that fall off will grow into another plant. As you dig, place all tubers immediately into plastic bags, seal or tie closed, and put in the trash. Do not put these in your compost! Don't set the tubers on your paths or on the lawn while you dig the rest--small tubers will undoubtedly fall off and spread the problem further. You can put them in a bucket or on a tarp. Then bag and trash all of it. 

You will not eradicate this from your mom's yard in one go. If you want to completely remove it, it will require digging the tubers at least annually for a few years until they are all gone. I recommend removing what you can now, and then digging the leftovers again next spring when the leaves are visible.  

I had this plant in a garden that I managed. I spent two years trying to get it under control. I am seeing it show up more and more frequently Wayne County gardens. Good luck!