• Albert Einstein's Most Intimate Letters to Engineer Michele Angelo Besso Uncovered

100 years ago, a renowned Nobel laureate decided to tour Spain. We are talking about the author of the theory of relativity Albert Einstein, who in 1923 visited Madrid, Barcelona, Zaragoza and Toledo, accompanied by a delegation of friends and important personalities. Among them, José Ortega y Gasset and Manuel Bartolomé Cossío. Also, according to the newspaper archive, the physicist traveled with his family, although it is not clear if he did so with any of his children, about whom little information is available.

According to various history books, Einstein was a tireless donjuan, who had countless affairs with women of all kinds and social classes. However, the genius was only married twice and, according to the letters he wrote between 1897 and 1919, he was truly in love with his first wife: the mathematician Mileva Mari, whom he met at the Zurich Polytechnic Institute in 1986.

Six years later, Mileva became pregnant. It is not known if having children was in her plans, but what is clear is that the news did not go down well at the prestigious institute and the young woman was expelled. Mari gave birth to her firstborn, but a long way from Einstein... In Serbia. What's more, it's unknown what exactly happened to the little girl. "At two years, Lieserl is lost. It may be that she was given up for adoption or that she has passed away," historian Ze'ev Rosenkranz told the BBC in 2021.

No news of her first daughter

Thanks to a letter signed by Einstein, there is evidence that Lieserl was born and that he had a close relationship with his mother during the first months. But it is not known if the scientist ever met her. On the other hand, the letters that Albert sent to Mileva show that they had a strong bond. But their relationship was not idyllic, as the Nobel laureate's parents did not believe Mari was "worthy" of their attentions.

But, against all odds, the couple continued their romance. After spending some time in Belgrade, Mileva, without her daughter, whose fate is unknown, moved to Bern, where her boyfriend was waiting for her. They married there in 1903. She took care of the house, he worked on his own affairs and the coexistence was great, according to the investigations. So much so that they decided to have another child.

Their two sons

In 1904 their son Hans Albert was born and in 1910, after moving to Zurich, the family welcomed Eduard. A very sickly child, who spent weeks in bed and suffered from terrible ailments. His lungs became swollen and he ended up bedridden. Despite this, Eduard was an excellent student and excelled in certain arts, such as poetry and piano. Something that made Einstein proud.

Sadly, the scientist only lived with his children until 1919. Albert fell in love with his cousin Elsa and left Mileva. However, she remained in touch with her children. Above all, with Eduard, with whom he debated his theories. The younger Einstein wanted to be a psychiatrist. But he was diagnosed with schizophrenia in 1933 and spent much of his life confined to clinics. He eventually died of a stroke in 1965.

Einstein, with his wife Elsa and two of their children. Getty

Hans Albert studied civil engineering at the Swiss Federal Institute of Technology in Zurich, obtained a doctorate in technical sciences, emigrated to the United States in 1938 and worked at the South Carolina Agricultural Experiment Station and the Department of Agriculture. Later, Einstein Jr. became a teacher. He was a professor of hydraulic engineering at Berkeley and his writings are still studied.

Your grandchildren

Hans Albert married Frieda Knecht in 1927, with whom he had three sons: Bernhard Caesar, who became a renowned physicist, Klaus, who died at the age of six from diphtheria, and David, who died at the age of one month. In 1958, Frieda also passed away and Hans Albert decided to rebuild his life with a woman named Elizabeth Roboz, with whom he had no children... So Bernhard Caesar, the eldest son of the family, was in charge of maintaining the lineage.

Bernhard was born and lived in Switzerland until he was eight years old, a time he shared with his grandfather. It was Einstein himself who recommended his family to fly to the United States, in order to escape Nazism. They spent a couple of years in South Carolina and later moved to Pasadena, where the young man developed his vocation.

And finally... Your great-grandchildren

In 1954, Bernhard — who worked as an engineer at companies such as Texas Instruments and Litton Industries — married Doris Aude Ascher and they had five children, who have tried to remain anonymous. Despite this, the internet has revealed their identities. Thomas Einstein, the eldest of them, is an anesthesiologist and lives in Santa Monica, while his brother Paul Michael lives in the south of France, where, married, he dedicates himself to composition and the violins, an instrument played by his great-grandfather.

The physicist, playing the violin. GTRES

According to numerous portals, Bernhard's third son - named Eduard Albert - is passionate about furniture and even has a number of stores in Los Angeles. And what about the other two? Mira Einstein, the only woman in the group, would devote herself to music, in Tel-Aviv, and Charles Quincy would have his permanent residence in Switzerland, where he would work as a spokesman for a major hospital. However, none of the five usually presents themselves as Einstein's heir. They prefer to keep a low profile.