Would you share your thoughts with me on this situation?

I have a 7 year old grandson, Jay, and his 1 year old sister, Zoey, a couple of times a week.
Jay is really intelligent. However, he uses his intelligence to push whatever buttons he can find, for attention, even if it’s negative attention (we’re all working on that.) However, I recognized what he was doing early on, and stashed all my buttons so he doesn’t know where they are. I have no problems with him. (His other gramma—his mom’s mom—on the other hand, once described him to me as “high maintenance,” which is not my experience.)

A couple of times he has told me that his other Gramma gets mad and yells at Zoey for “hiding” her bottles (now sippy cups.)
I said “Jay…Zoes doesn’t hide them. She just drops them where ever and doesn’t understand the requests to find them. That’s all. You can’t yell at a baby for that!”
He said, “Oh, she hides them! The other day Gramma found a sippy cup in the fridge and it was empty!” His tone mimicked an adult who would say that like, “What kind of idiot puts an empty sippy cup in the fridge??”
I looked at him and said, “Jay…Zoey can’t open the fridge.”
He went very still and very quiet.
I said, “Jay…have you been hiding Zoes sippy cups?”
He said, “No,” but I wonder. I mean, that’s a button his gramma has for all the world to see. Piece of cake to push it.

The other day I came around the corner and Zoey jumped like she’d been electrocuted (!) and there was a pile of dirt at her feet from a plant I have. I said, “Zoey! You know you shouldn’t do that!” and I put her in “time out.” I set her on the bottom step of the stairs and shook my finger at her and scolded her for a few seconds. Then I had her come over and help put the dirt back in the plant. Well, that didn’t work as planned. She had more fun putting the dirt back in than she did taking it out! Her dad walked in as we were working. So we got most of it in, then he and I went out on the deck.
Well, a couple of minutes later Jay yelled, “She’s taking the dirt out again!”
So we went back in, and Zoes got in trouble again, this time by her dad.

But now….I’m wondering….Are you wondering what I’m wondering? Is this something I should discuss with my son?