If you're talking about John Parke Custis, he was born on November 27th, 1754. From what I know, he didn't change his last name to Washington, but he was however, the stepson of George Washington.
Martha Parke Custis Peter was born in 1777.
Edward Parke Custis Lewis was born in 1837.
Elizabeth Parke Custis Law was born in 1776.
George Washington Custis Lee was born on 1832-09-16.
Eleanor Parke Custis Lewis was born on 1779-03-31.
Mildred Childe Lee was born on February 10, 1846 at Arlington, the plantation built by her maternal grandfather, George Washington Parke Custis.
Martha was born Martha Dandridge. She became Martha Dandridge Custis when she married her first husband, Daniel Parke Custis, in 1750. After Daniel's death in 1757, she married George Washington on January 6, 1759. Two of her children by Custis were still living at the time : John "Jacky" Custis was 4, and Martha ("Patsy") Custis was 2.
Martha's two children were by her first husband, Daniel Parke Custis. John ("Jacky") was 4, and Martha ("Patsy") was 2 when Martha and George were married in 1759. George and Martha raised Jacky and Patsy; Patsy died at age 17 and Jacky married Eleanor Calvert, and had four children. Two of Jacky's children were raised by George and Martha.
Martha (Custis) Washington was a widow when she married George: she had four children with her first husband, but only two of them survived into the time when she re-married. Those two were John (Jacky) Parke Custis, who lived to be 27 years old and died in 1781; and Martha ("Patsy") Parke Custis, who died in 1773 when she was only 17. George and Martha Washington did not have any children together.
He was born on Nov. 27, 1754
A widow, Martha Custis, born Martha Dandridge