“There’s a Confederate Memorial in Arlington.”
The last private owners of Arlington were Colonel and Mrs Robert E Lee.
Lee’s wife was the daughter of GW Parke Custis and they inherited the property upon his death in 1857. The only time that they had a house of their own.
Parke Custis was Martha Washington’s grandson. Martha and George Washington had raised Parke and his sister at Mount Vernon after the death of their father.
The estate was stolen by the federal government from the Lee family under the fabricated claim they had failed to pay taxes on it (large amounts of Southern property were stolen from their owners by the Union on the same fabrication).
https://en.wikipedia.org/wiki/United_States_v._Lee_(1882)