The family moved to Finchley, north London, in 1844 where Dr Stephens bought and renovated a large residence named Grove House, in Ballards Lane.

The outbuildings of Grove House were used by the inventor as a laboratory for research and manufacture of ink and wood stains; thus Henry Charles grew up among his father's work and learnt the business from a young age.

Marnock's plans included lawns, ponds, mounds, paths and steps, and a walled kitchen garden and park-keeper's dwelling known as The Bothy (1882).

Stephens added a water tower with adjacent building, a lodge, coach house and stable block and arranged for a number of rare trees to be planted throughout the grounds.

In February 1900 his eldest son, Henry O'Reilly Stephens, sought to enforce an agreement made with his father in June 1893 whereby he would be paid £25,000 or interest of 6% per annum of that sum for the rest of his life in the event of him leaving the company.