Question: What year was Prince Henry of the Netherlands's mother born?

Context articles: Prince Henry Heights, Queensland
Prince Henry the Navigator Park
Prince Henry's Grammar School, Otley
Prince Henry of the Netherlands (1820–1879)
Princess Amalia of Saxe-Weimar-Eisenach
Princess Marie of Prussia (1855–1888)
Prince Henry's High School
The Speeches at Prince Henry's Barriers
Escola Superior Náutica Infante Dom Henrique
Anna Pavlovna of Russia

Prince Henry Heights is a suburb of Toowoomba, Queensland, Australia, located 5 km east of the city centre.
 It was named for Prince Henry, Duke of Gloucester, who served as Governor-General of Australia from 1945 until 1947; the suburb's boundary road had been known as Prince Henry Drive well before 1945.
Prince Henry the Navigator Park on Pope's Island in New Bedford, Massachusetts is dedicated to Prince Henry the Navigator, and was created in 1994.
 It was a gift to the city from the Prince Henry Society of New Bedford and the Portuguese government.
Prince Henry's Grammar School (Specialist Language College), also known as Prince Henry's, is a secondary school and sixth form established in 1607 in the market town of Otley, West Yorkshire, England.
 The school teaches boys and girls between the ages of 11 and 18 and has around 1,400 pupils and 84 teachers.
 It retains a high position within regional league tables.
 Leading departments include Art, English, History and Science.
 Despite the name, Prince Henry's is now a state-funded academy school.
Prince William Frederick Henry of the Netherlands (Dutch: Willem Frederik Hendrik; 13 June 1820 – 14 January 1879) was the third son of King William II of the Netherlands and his wife, Grand Duchess Anna Pavlovna of Russia.
 He was born at Soestdijk Palace.
Amalia Maria da Gloria Augusta (Ghent, 20 March 1830 — Walferdange, Luxembourg, 1 May 1872), Princess of Saxe-Weimar-Eisenach, was the first wife of Prince Henry of the Netherlands, son of king William II of the Netherlands.
Princess Marie of Prussia ("Marie Elisabeth Louise Frederika of Prussia"; 14 September 1855, Marmorpalais, Potsdam – 20 June 1888, Dresden), was a princess of the House of Hohenzollern.
 She was the daughter of Prince Frederick Charles of Prussia and later became second wife of Prince Henry of the Netherlands then the first wife of Prince Albert of Saxe-Altenburg.
 She was also the great-niece of Wilhelm I, German Emperor.
Prince Henry's High School, formerly Prince Henry's Grammar School is a secondary school with academy status in Evesham, Worcestershire, England.
 It is a co-educational high school, in which there are about 1260 students enrolled, aged between 13 and 18.
 It is situated in the north of Evesham off the A4184, near the junction with the B4624, adjacent to the north of the railway, and serves the town of Evesham and surrounding villages.
 A 2010 Ofsted report accorded the school a Grade 1 (outstanding)
The Speeches at Prince Henry's Barriers, sometimes called The Lady of the Lake, is a masque or entertainment written by Ben Jonson in honour of Henry Frederick, Prince of Wales, the son and heir of King James I of England.
 The speeches were performed on 6 January 1610 in conjunction with the ceremony known as Prince Henry's Barriers.
The Infante D. Henrique Nautical School (Portuguese: "Escola Náutica Infante D. Henrique/Escola Superior Náutica Infante D. Henrique" ) is a school of higher education dedicated to naval and nautical studies, situated in the civil parish of Oeiras e São Julião da Barra, Paço de Arcos e Caxias, the municipality of Oeiras, in the Portuguese district of Lisbon.
 Literally, the Prince Henry Nautical College (and abbreviated as "ENIDH") the school was named for the Portuguese prince Henry the Navigator and specializes in maritime studies.
Anna Pavlovna of Russia (Russian: Анна Павловна ; Dutch: "Anna Paulowna"; 18 January 1795 — 1 March 1865) was a queen consort of the Netherlands.