"we are sure that she puts laud'num in his milk"

Public DomainLaudanum - Credit: Cydone, Wikimedia Commons
 Laudanum is a solution of opium and alcohol, also known as tincture of opium. It is highly addictive.

It was available in Britain from the late 17th Century onwards, and was used for pain relief, inducing sleep, and for the treatment of various medical ailments in both adults and children.

Thomas de Quincey (1785-1859) gave an account of his addiction to laudanum in his book Confessions of an English Opium-Eater (1821).