Clarissa and Peter had two children, names not yet known.
Miranda and George had no children.
Alice's mother might have been Sarah, Archibald's second wife.
Marcus was a math professor at Hamilton College in NY.
Philena's birthdate is given as 1 Sep 1833. Because she married Marcus on 9 May 1833, it is likely that her actual birthdate was 1803 or 1813. Or some other year.
Also, her last name is not the same as that of her father. She might have had it changed. (From other information given in the source, it seems likely that she was rich, spoiled, and eccentric, although this is only conjecture. However, it would account for the last name.