[2] On 6 July 1815, Whitbread's father took his own life, whereupon his two sons, William Henry (then aged 20) and Samual Charles (19), inherited the family business and estates.

According to Dreyer and Turner (1923) he was most excellent in this position, leveraging his experience from running the family business: "He was an absolute terror to defaulters in arrear with their contributions, and used to visit them personally and ask them to explain their conduct before he recommended the Council to expel them".

In the early 1840, Whitbread built an observatory on his grounds, and with the help of his gardeners, made carefully astronomical and meteorological observations.

On 9 December 1815, months after his father's death, the principal gamekeeper Charles Dines at the family seat Southill Park was murdered by a poacher.

After his elder brother William Henry Whitbread died without heirs in 1867, Samuel Charles inherited the family firm and estates.