The Hon. Mr. and Mrs. James Tollemache are the parents of a daughter, Sylvie.
Mrs. Tollemache was born Princess Florence von Preussen, the daughter of HRH Prince Nicholas von Preussen and his former wife, the Hon. Victoria Mancroft. (This was a morganatic marriage, and, Nicholas' children are not HRH. In England, the title is used a social convenience.)
The couple married on May 10, 2014.
James is the younger son of Lord and Lady Tollemache.
The March 11, 2016 Daily Telegraph has the announced
"Sylvie Beatrice Selina Tollemache was born as first daughter and first child to James Tollemache and his wife Florence, née von Preussen at the Guys and St Thomas Hospital on March 2nd 2016."
Beatrice and Selina are certainly in honor of Florrie's sister, Beatrice von Preussen, and James' sister, the Hon. Selina Hopkins.