Vance will be the first VP to have a child while in office since the 1870s

• The last vice president to have a child while in office was Schuyler Colfax, who served under President Ulysses S. Grant. Colfax and his wife, Ellen, had a son, Schuyler Colfax III, in April 1870.

Driving the news: The Vances are expecting a boy in July, the couple said via a statement shared Thursday on X. They currently have three children: Ewan (8), Vivek (5) and Mirabel (4).

• "During this exciting and hectic time, we are particularly grateful for the military doctors who take excellent care of our family and for the staff members who do so much to ensure that we can serve the country while enjoying a wonderful life with our children," Usha Vance posted on X.
• In response to the post, the White House on X said: "The most pro-family administration in history."

State of play: It's unclear how many vice presidents have had children while in office, as birth and death records from the nation's early days are often missing or incomplete.

• But there are records for some births, including Vice President John Calhoun and his wife, Floride, who welcomed two children, James (1826) and William (1829).
• Calhoun served as vice president for two different administrations, so James was born during President John Quincy Adams' tenure, and William during President Andrew Jackson's administration.

• Hannibal Hamlin, Abraham Lincoln's vice president, and his second wife, Ellen, had a son, Frank, in 1862.

Zoom in: It's not just vice presidents who have had children while in office.

• President Grover Cleveland and first lady Frances Cleveland had two daughters during his two terms — Esther (1893) and Marion (1895).
• Esther remains the only child of a president born in the White House. Marion was born in Massachusetts.
• President John F. Kennedy and first lady Jacqueline Kennedy's third child, Patrick, was born prematurely in August 1963, but died hours later.

Go deeper: Who is Usha Vance, wife of Trump VP pick J.D. Vance