His mother was Júlia Bossányi, who took an interest in his education, with home tutor Jeromos Nagy teaching him German, Latin, and history.

He also linked heredity (vererbung) with health and vigor independently of external factors, stressing the role of inbreeding (combined with strong selection) in stabilizing character inheritance for preserving or developing new races.

To illustrate the concept he used sheep, chicken, cattle and horse breeds as examples, although he also applied it to the human species by considering populations of isolated Hungarian villages, in which he had observed degenerative mental and physical characteristics.

He also noted the consequences of selection and its role in heredity, believing that variability and his postulated laws of genetics were connected, acting together in breeding as well as in the natural processes controlling populations of different animals, including humans.

Festetics, however, was ultimately hindered by the complex nature of his study traits, aspects of wool quality that are now known to be polygenic.