Confront lady who lets her dog poop on the sidewalk?

There is a sidewalk in my neighborhood lined with trees. It’s lovely to take a walk down. Every day I walk my two kids down it and let them ride their bikes. About once a week for the past few months I have noticed someone had been letting their dog poop all over the pathway. Not in the grass to the side, or in the trees, but on the sidewalk. It’s been annoying to have my kids have to avoid rolling their bikes into it.

Today I noticed there was a lady in front of me, at the far end of the walkway with a big German shepherd she was having trouble controlling. I recognized her as my direct neighbor. Single lady who lives alone with her dog and has never said a word to me. I keep walking and I’m getting closer to her and her dog she is struggling with. And then I see it, the dog squats, and poops all over the sidewalk. She pulls him across the street and we make eye contact so she knows I know saw. She made no attempt to pick it up. And now I’m thinking she has been the one letting this dog poop all over the sidewalk this entire time. I stared at her as she dragged her dog away as quickly as possible. But I didn’t say anything because I had my kids, and he has a massive out of control dog I’m scared of. She has always been a quiet neighbor and I hate to ruffle feathers. But omg I find this so rude. People love walking down this walkway with the pretty trees and she’s just letting her dog poop all over it. Would you say something to her?