sentences:  While Henry and Catherine would eventually produce 10 children together, and despite the occasional affair with such as Philippa Duci, Janet Fleming, and Nicole de Savigny, Diane de Poitiers would remain Henry's lifelong companion.For the next 25 years, she would be the most powerful influence in his life and the most powerful woman in France.Based on allusions in their correspondence, it is generally believed that she became his mistress in 1534, when she was 35 years old and Henry was 15.