Shew is actually not our dog. We dog-sit her during the day while our daughter works to buy doggie goodies for her.
We were taking charge of her for an extended period of four days. On the third day she was sure that it was time for her person to pick her up.
She began whining at the door. Not just a squeak or two but serious whining. Then she walked over to her halter hanging by the door, that she uses when she rides, stood on her hind feet and pointed out to me that she should have the the halter put on. Then back to the door she went to whine with more feeling.
Threat of dark of night and all manner of other suggestions failed to produce the desired quiet.
She seemed to think that this was a reasonable equation. The wheeled creature needed to be there for her to ride in it and for her person to be present.
After that she was quiet and slept the rest of the day.