His brother Alexandre, vicomte de Beauharnais, married Josephine Tascher de la Pagerie (afterwards the wife of Napoleon Bonaparte) and had two children by her - Eugene de Beauharnais and Hortense, who married Louis Bonaparte, king of Holland, and became mother of Napoleon III.
In 1802 the First Consul married him to Hortense Beauharnais, a forced union which led to most deplorable results.
At the close of the year Louis went to Paris, partly in order to procure a divorce from Hortense and partly to gain better terms for Holland.
Meanwhile the Countess Potocka had established herself in Paris, but Charles de Flahaut had by this time entered on his liaison with Hortense de Beauharnais, queen of Holland.
He was assiduous in his attendance on Queen Hortense until the Hundred Days brought him into active service again.
Of the two other sons of Louis Bonaparte and Hortense, the elder, Napoleon Charles (1802-1807), died of croup at The Hague; the second, Napoleon Louis (1804-1831), died in the insurrection of the Romagna, leaving no children.
It is certain that, after the abdication and exile of Louis, Hortense lived in France with her two children, in close relation with the imperial court.
After Waterloo, Hortense, suspected by the Bourbons of having arranged the return from Elba, had to go into exile.
Hortense supervised her son's education in person, and tried to form his character.
Hortense hurried to the spot and took steps which enabled her to save her second son from the Austrian prisons.
At the Elysee, Morny, adulterine son of Hortense, a hero of the Bourse and successful gambler, supported his half-brother by his energy and counsels.
The marriage of his widow Josephine to Napoleon Bonaparte in March 1796 was at first resented by Eugene and his sister Hortense; but their step-father proved to be no less kind than watchful over their interests.
Bonaparte brought hint back to France in the autumn of 1799, and it is known that the intervention of Eugene and Hortense helped to bring about the reconciliation which then took place between Bonaparte and Josephine.