What education did the Lincoln boys receive?

[Dan Pearson]

In Pendel's reminiscences he states that he was at his post at the White House the night of April 14, 1865. When her received word of the president being shot, from Isaac Newton, Pendel went upstairs to inform Robert Lincoln of the news. Pendel then waited at the White House for Tad to return, and it was Pendel to whom Tad said, "They have killed Papa Dead," (or "they have killed Papa-day," depending on your interpretation). Pendel then got Tad calmed down a bit, and put him to bed and lay with him in the President's room.