When I told Ralph about his father and the dream, he felt that (because he's had his own dreams about him, over the many past 10 years since he passed), that as I did, it was him, (or the him we recalled and knew)
............The "old car" he originally pulled up in, was a pun for his "older manifestation at the end of his life".
The fact that the car "disappeared" but he stayed behind to go into the building and "be seen" publically, and that's why I ran to get the camera to photograph proof he had been there.........means that
the symbol of the "older car", is showing us he has changed, and is no longer that older person, mean, embittered and angry.
He was "smiling, waving and happy".....as he went into that building.
The part of my wanting the camera for "proof", is because as with the UFO Ralph & I saw in 1997 near our home, we always said, it was so sad, we didn't think to take our camera out with us and photograph it that night, (a video camera)he had then.
So, when we moved to this new house, we bought a new smaller, easier to take, video camera, just in case we ever saw a UFO again, we'd have it ready......and available.

So in this light, it makes sense, I ran to get the camera......
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addition to the dream:
Although it seemed the girls, were older teenagers (the 2 older ones), the youngest one, who today, for the past 10 years has been "estranged" from all; in this dream was very little.
She was with me, running to see her grandfather, BUT, I recognized that she had a "load" in her pants, meaning, she needed to be changed, as it smelled.......
I told her to go in with the others, see her grandfather, and then, I'd change her in the ladies' room, and she seemed okay with that idea.,kind of relieved I think that I said this to her.
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Interpretation of last part added:
..................It speaks for itself.

as I see her behavior for the past 10 years, as "stinking".