Father: Philip III
Mother: Margaret of Austria

Sisters: Anne (married Louis XIII of France)
           Maria Anna

Wife 1 (1621): Elizabeth de Bourbon (sister of Louis XIII of France)
Wife 2: Mariana of Austria (daughter of Ferdinand III and of Philip's own aunt)

Daughter (by Elizabeth): Maria Theresa (married Louis XIV of France)
Son (by Mariana): Charles II
Daughter (by Mariana): Margaret Theresa (wife of Leopold I)