He married Elisabeth Willwerth on October 21, 1845 in Jöhlingen at the Church of St. Martin.

The bride was christened on May 21, 1821 in Jöhlingen at the Church of St. Martin.

Her parents were Franz Joseph Willwerth and Barbara Rüssel.

Sebastian died on May 25, 1890 in Boston, Massachusetts.
Elisabeth died on April 25, 1890 in Boston.

They were the parents of the following children:

Jakob

was christened on May 28, 1846 in Jöhlingen.

Wilhelm

was christened on August 1, 1847 in Jöhlingen.

Johann

was christened on November 1, 1848 in Jöhlingen.

Maria Eva

was christened on September 30, 1849 in Jöhlingen.

Karoline¹

was christened on December 8, 1850 in Jöhlingen.
She married Rudolph Farrenkopf on May 20, 1869 in Boston at Holy Trinity Church.

Lorenz

was christened in April of 1852 in Jöhlingen.

Magdalena

was christened on March 22, 1853 in Jöhlingen.

Barbara

was christened on March 22, 1853 in Jöhlingen.

Elisabeth

was christened on November 21, 1854 in Jöhlingen.
She may have died on March 22,1855 in Boston.

Gabriel A.

was christened on April 27, 1856 in Boston at Holy Trinity Church.

Andreas

was christened on August 29, 1857 in Boston at Holy Trinity Church.
He died on September 22, 1858 in Boston.

John

was christened on November 16, 1858 in Boston at Holy Trinity Church.

Aloysius

was christened on June 16, 1860 in Boston at Holy Trinity Church.
He died on October 2, 1860 in Boston.

Maria Anna

was christened on July 19, 1861 in Boston at Holy Trinity Church.
She died on November 23, 1861 in Boston.

Sebastian Francis

was christened on January 18, 1864 in Boston at Holy Trinity Church.
He died on September 13, 1890 in Boston.

Sebastian, his wife, and daughter, Karoline, were enumerated in the 1855 Massachusetts state census. At that time they were residing in the East Boston district of Boston at the same address as several Willwerths, who were Sebastian's in-laws. Based on the christenings of those children who were born in Germany it seems that most died as infants or as young children, since it is likely that only 2 of the children accompanied their parents to America circa early 1855 and that only 1 child was listed in the 1855 census.

1. She died died on December 8, 1909 in Boston and was buried at Holyhood Cemetery in Brookline, Massachusetts.