Ernesto Guevara de la Serna was born on 14th June 1928 in Rosario, in the province of Santa Fé, in Argentina.
His father was Ernesto Guevara-Lynch (with Spanish and Irish ancestry), his mother was Celia de la Serna y de la Llosa (with Spanish ancestry), both of them coming from Buenos Aires. Celia was an extraordinary woman, intelligent, attractive, elegant and daring (she wore trousers, smoked and had short hair when it was unusual for women). She spoke French fluently and she even taught this language to Ernesto. She was always very close to her first son and this close relationship remained until her death in 1965. (She suffered from breast cancer several times.)
They were atheists as they detested the clergy and their hypocricy and even though they went to Sunday mass sometimes, it was social occasion for them when they could meet their friends. They always helped the poor and were ready to help everyone who fought for their own home country. Ernesto Guevara was even a member of the group, Acción Argentina, that helped to discover Nazi spies, hiding in Argentina.

In 1928, after a secret wedding, the couple was living in their yerba mate plantation in Puerto Caraguatay (yerba mate is a kind of tea, similar to green tea and Che loved it, drinking it throught his whole life). They were travelling back to Buenos Aires for the birth of their first child, but the baby couldn't wait anymore and he was born in the middle of the journey. 
The happy parents called their son Teté, then Ernestito to distinguish him from his father - even when he was already a grown-up man.  
The little boy spent his first two years on the plantation in the house that his father designed and built. The family wasn't that rich, the father always had to work for the money, but the parents were educated people so they wanted their children to study and receive a university degree. (Four of the five Guevara children did: Ernesto was a doctor, Celia and Ana María became architects, and Roberto became a lawyer. Only Juan Martín chose to be a guerrilla fighter instead of obtaining a degree.)
In 1930 for the birth of Celia, the second Guevara child, the family moved back to Buenos Aires, then they returned to the plantation. Here Ernesto began to suffer from asthma - this affected his whole life, suffering from this disease till the last day of his life. (The other four Guevara children had asthma too, but they had a very mild version.) The family had to move and they chose Buenos Aires because it had a dry air. They hoped it would improve Ernesto's health condition.
In 1932 Roberto, the third Guevara child was born and soon they moved again - this time, into the hills of the province Córdoba. Ernesto's health had its ups and downs, so they started a new life in Alta Gracia - from 1933 to 1944.

Ernesto felt much better, he could breathe much easily, though his less often asthma attacks were violent and confined him to bed for longer periods. His parents encouraged him to live a normal life and he decided that he would not let it bring him down or interfere with anything that he wanted to do.
In spite of asthma, he studied (at home by the help of his mother as he couldn't attend school regularly until he was nine years old), read passionately, spoke and read French fluently, could tell French poems by heart, and he did sports, like swimming and ball games, even rugby - he always had his asthma inhaler at hand and during matches one of his friends carried it running along the sidelines in order to be near Ernesto when he would need it. He earned one of his nicknames, Fúser (meaning Furious) on the rugby field and he was so fierce and wild while playing the game.) His father taught him to play chess and he attended competitions from the age of twelve.
He was a popular boy, he had a lot of friends - one of them, Carlos "Calica" Ferrer was the man, with whom he took his second journey around South America. They were close friends - not only because both of them were tone deaf and unable to dance, still they were popular with girls.
In 1934 Ana María, the fourth Guevara child was born. The family soon moved to the Villa Nydia that is the Che Guevara Museum today, while they spent the summer holidays in Mar de Plata, a seaside resort.

In 1941 Ernesto finished his primary education at Escuela Pública San Martín, then in 1942 he continued his studies at Colegio Nacional Deán Funes, in Córdoba city. Here he met and made friends with Tomás Granado - whose brother, Alberto, also became his friend and they did the famous motorcycle journey around South America together. The boys played rugby together and loved reading.
The whole family moved to Córdoba in 1943, a little before the birth of the fifth Guevara child, Juan Martín. They had a house in Calle Chile.



In 1945 Alberto was taken into custody during the student rebellions and Ernesto visited his friend with a packet of food. There happened when he announced that he would join the demonstrations only with a gun in his hand as he would not be a fool to face the policemen holding revolvers unarmed.
In 1946 the Guevara family returned to Buenos Aires for good, though Ernesto remained in Córdoba to finish his studies. He had a job in the analysis department of the Provincial Roads Directorate. Next year he completed his Baccalaureate and returned to his family - only to hear sad news.
His beloved grandmother became very ill and soon died - Ernesto stayed with her in her last seventeen days. He was devastated by her death and furthermore, his mother had a serious operation for breast cancer. He decided to enrol in the Faculty of Medicine at the University of Buenos Aires.