He was John Quincy Adams.

By chance I was on the floor of the House when he fell in his place, and followed the excited and tearful throng when they bore him into the Speaker's Room, kneeling by the side of the sofa with an improvised fan and crying as if my heart would break.
One day in the spring of 1851 my father took me to a little hotel on Pennsylvania Avenue near the Capitol and into a stuffy room, where a snuffy old man wearing an ill-fitting wig was busying himself over a pile of documents.

He turned about and was very hearty.
"Aha, you've brought the boy," said he.
And my father said: "My son, you wanted to see General Cass, and here he is." My enthusiasm over the Cass and Butler campaign had not subsided.
Inevitably General Cass was to me the greatest of heroes.

My father had been and always remained his close friend.

Later along we dwelt together at Willard's Hotel, my mother a chaperon for Miss Belle Cass, afterward Madame Von Limbourg, and I came into familiar intercourse with the family.
The general made me something of a pet and never ceased to be a hero to me.