Conversation so far:
How come Cornelius Vanderbilt focussed on steamboats?
That year he faced opposition by a steamboat operated by Daniel Drew, who forced Vanderbilt to buy him out.
How did he make all his money?
After Thomas Gibbons died in 1826, Vanderbilt worked for Gibbons' son William until 1829.
did he get along with Gibbon's son William?
CANNOTANSWER.
Why did he stop working with Gibbon's son?
In 1831, he took over his brother Jacob's line to Peekskill, New York, on the lower Hudson River.

Question: Why didn't Vanderbilt help with the Peekskill line?
Self-contained rewrite: Why didn't Cornelius Vanderbilt help with the Peekskill line?