Gerard Bicker (I) van Swieten

[2] He had four sisters, three of whom were married to Amsterdam mayors; Margaretha ⚭ in second marriage to Cornelis Geelvinck, Alida ⚭ to Lambert Reynst and Elisabeth ⚭ to her uncle and 2nd cousin Andries de Graeff.

His brothers-in-law where important and loyal political allies to Grand pensionary De Witt.

[2] After the death of his second wife, he remarried with Jonkvrouw Catherina van Sijpesteijn for the third time in 1665,[3] but they had no further children.

Gerard Bicker van Swieten became commissioner in 1656 and captain of the Amsterdam schutterij (Citizen Guard) in 1662.

[2] In 1669, through the intercession of De Witt, he obtained the position of Statutory auditor of the Court of Audit of the domains of Holland and West-Friesland (Dutch: Rekenmeester der Grafelijke domeinen van Holland en West-Friesland / Meester ordinaris van de Rekenkamer van Holland en West-Friesland).