1) The Aged Parent is great Expectations is Wemmick's father. Each night, the aged parent wold perform part of a ceremony that he and his son shared. The Aged would fire up the poker from the fire until it couldn't get any hotter, and Wemmick would then take the poker to the battery and set off the cannon he's named a "stinger."
2) Pip would take Magwitch home personally, and then he and Herbert would consult and plan the actions they were going to take to get Magwitch out of the city.
"Another night-consultation with Herbert after Provis was gone home (I always took him home, and always looked well about me), led us to the conclusion that nothing should be said about going abroad until I came back from Miss Havisham's." (Chapter 43)