Ok, evereything was very easy. My mom arrived to IAD. The flight attandant show her the mens with wheelchairs. Then they go to the immigration/passport control. There was lot off passengers, that was a busy day. Than go together to the carousel. These bag has priority, the man went to find my mothers bag, and than go throu costum, and then to exit gate, where my sister wait they.
On the board said not to use mobilphone until end costum check.
It was very easy without any stress for my mother. She gave 4 USD to man with wheelchair ( she had nx50 USD and 4x1USD What do You think it was enough, or more be better? ).

If anybody has this "problem" : how can an aged an non english speaking person travel by plane: it's very easy with wheelchar service.^

For Annandaler: So how little the Earth: my mother went to Annandale to my sister