During his upbringing, he regarded himself as male, and wrestled with his brother with the approval of the father, and was generally referred to as Lilla Fröken Herrn ("Little Miss Mister").

After this, his father took him to be examined by a physician, Anders Johan Hagströmer, professor in anatomy and surgery in Stockholm.

[2] In July 1825, the physician issued a statement were Bruce was declared to be a "hermaphrodite" (intersex) whose male genitals were more developed than the female.

He also visited the capital of Stockholm as a man, drank alcohol and smoked in public, which was then only acceptable for males.

Bruce also took part in the drills in the local militia, and regarding it as a way to prove his masculinity, he made such efforts that he received praise from his commanders.

Bruce has been pointed out as the role model for the character Tintomara in the novel Drottningens juvelsmycke by Carl Jonas Love Almqvist.