He was appointed a teacher in languages, mathematics, geography and Belgian history at the veterinary college in Brussels' Rue Terarken.

Heger met Mlle Claire Zoë Parent (1804 – 1887), the directress of the neighbouring girls’ boarding school in the Rue Isabelle, where he began teaching.

Their time at the boarding school was cut short when Elizabeth Branwell, their aunt, who joined the family after the death of their mother to look after the children, died of internal obstruction in October 1842.

Heger had first shown them to Elizabeth Gaskell when she visited him in 1856 while researching her biography The Life of Charlotte Brontë, but she concealed their true significance.

Paul Heger, their son, and his sisters, gave these letters to the British Museum, and they were shortly after printed in The Times newspaper.