I know you don't have anything with you right now, but if this is something that might be happening often this Summer, you can invest in a child gate, or even an X-pen for a dog, which you would put around the stairs, to keep the little one away from them.
If you have the steps cutting down in the middle of the room, you may want to get a piece of plywood, that you can lay over the steps, to hide them. Of course, that means more work for you, when you want to go in/out, but I'm sure that you are more concerned about the safety of the Grand-daughter.
We've got a 3 year old, and we worry too! Fortunately, the steps are alongside the kitchen cabinet, so sorta out of site...but we still worry.
Good Luck:)
Bill & Claudia / DD Jenn / DS Chris / GS MJDogs: Sophie, Abby, Brandy, Kahlie, Annie, Maggie, Tugger & Beau 🙂RIP: Cookie, Foxy & Gidget @ Rainbow Bridge.😞2000 Winnebago "Minnie" 31C, Ford V-10
Purchased April 2008:B FMCA# F407293
The Pets