This is more from J.C. Mollema's "Honor Roll".
Sier de Liefde
Sier de Liefde lived from 1595 to December 1652. He served the Admiralty of the Maze (Rotterdam). He was a captain in 1636 and a Schout-bij-Nacht in 1651.
In 1620, he convoyed the fishing fleet and repelled an attack, by two Dunkirkers at Texel. In 1637, he recaptured two prizes from the Dunkirkers. In 1638, he fought an action against two Dunkirkers. In 1639, he fought under Maarten Harpertszoon Tromp at the Downs. In 1641, he commanded the Witte Engel (30 guns) under Gysels in the operation off Portugal, fighting at the Battle of St. Vincent. In 1643/'44, he convoyed the fishing fleet. In 1652, he fought at the Battles of Dover and Dungeness. He was wounded at the last battle and died.
Douwe Aukes was born about 1610. From Mollema, we don't know when he died. He served the Admiralties of Friesland and Amsterdam.
In 1652, he distinguished himself as captain of the Vogelstruys in the Battle of Plymouth. In 1657, he was a skipper in the Mediterranean Sea. In 1665, he was a merchant at Amsterdam. In 1666, he supposedly went to the East Indies.