Question: Alan Chipp is the younger brother who was the inaugural leader of what party?

Context articles: Don Chipp
Alfred Seabrook
Alan Chipp
Rogers baronets
Milton Margai
Aliaskhab Kebekov
István Csurka
William McWilliams
János Kis
Boreel baronets

Donald Leslie Chipp, AO (21 August 192528 August 2006) was an Australian politician, and the inaugural leader of the Australian Democrats.
Alfred Charles Seabrook (5 April 1867 – 11 June 1939) was an Australian politician.
 Born in Hobart, he was educated in Ireland, after which he became a builder and contractor.
 In 1922, he was elected to the Australian House of Representatives as the Nationalist member for Franklin, defeating Nationalist-turned-Country Party MP and inaugural leader of the Country Party William McWilliams.
 He held the seat until his defeat by McWilliams, running as an independent, in 1928.
 In 1931, he was elected to the Tasmanian House of Assembly as a United Australia Party member for Franklin, holding the seat until 1934.
 Seabrook died in 1939.
Alan Chipp (born 9 January 1937) is a former Australian rules footballer who played with Fitzroy in the Victorian Football League (VFL).
 He is a younger brother of politician Don Chipp.
The Rogers Baronetcy, of Wisdome in the County of Devon, was a title in the Baronetage of England.
 It was created in 1699 for John Rogers, a merchant and Member of Parliament for Plymouth.
 His son, the second Baronet, and grandson, the third Baronet, also represented Plymouth in Parliament.
 The latter was childless and was succeeded by his younger brother, the fourth Baron.
 He was a Captain in the Royal Navy.
 His son, the fifth Baronet, sat as Member of Parliament for Plymouth.
 He was succeeded by his eldest son, the sixth Baronet.
 He sat as Member of Parliament for Callington and was also a composer.
 He was unmarried and was succeeded by his younger brother, the seventh Baronet.
 The latter was succeeded by his eldest son, the eighth Baronet.
 He was a prominent civil servant and notably served as Permanent Under-Secretary of State for the Colonies from 1860 to 1871.
 In 1871 he was elevated to the Peerage of the United Kingdom as Baron Blachford, of Wisdome and of Blachford in the County of Devon (Blachford House, Cornwood, near Ivybridge).
 He died childless in 1889 when the barony became extinct.
 He was succeeded in the baronetcy by his younger brother, the ninth Baronet.
 The latter was in his turn succeeded by another brother, the tenth Baronet, on whose death in 1895 the baronetcy became extinct as well.
Sir Milton Augustus Strieby Margai PC (7 December 1895 – 28 April 1964) was a Sierra Leonean doctor and politician who served as the country's head of government from 1954 until his death.
 He was titled Chief Minister from 1954 to 1958 and then Prime Minister from 1958 onwards.
 Margai studied medicine in England, and upon returning to homeland became a prominent public health campaigner.
 He entered politics as the founder and inaugural leader of the Sierra Leone People's Party.
 Margai oversaw Sierra Leone's transition to independence, which occurred in 1961.
 He died in office aged 68, and was succeeded as prime minister by his brother Albert.
Aliaskhab Alibulatovich Kebekov (Russian: Алиасхаб Алибулатович Кебеков; 1 January 1972 – 19 April 2015 ), also known as Ali Abu Muhammad (Russian: Али Абу Мухаммад ), was a Dagestani militant Islamist in Russia and the leader of the Caucasus Emirate following the death of inaugural leader Dokka Umarov.
 Following in the same religious tradition as Umarov, he adhered to the ideology of Salafism.
 The United States Department of State added Kebekov to its list of Specially Designated Global Terrorists on March 25, 2015.
 On 19 April 2015, Kebekov was killed by Russian security forces during special operations in the settlement of Gerei-Avlak in Buynaksk.
 An Avar by nationality, Kebekov was the first non-Chechen to lead the North Caucasus insurgency.
István Csurka (27 March 1934 – 4 February 2012) was a right-wing Hungarian journalist, writer and politician.
 He was the founder and inaugural leader of the Hungarian Justice and Life Party (MIÉP) from 1993 until his death.
 He was also a Member of Parliament from 1990 to 1994 and from 1998 to 2002.
William James McWilliams (12 October 1856 – 22 October 1929) was the inaugural leader of the Country Party of Australia.
János Kis (born 17 September 1943) is a Hungarian philosopher and political scientist, who served as the inaugural leader of the liberal Alliance of Free Democrats (SZDSZ) from 1990 to 1991.
The Boreel, later Boreel Baronetcy, of Amsterdam in the Netherlands, is a title in the Baronetage of England.
 It was created on 21 March 1645 for William Boreel.
 He was Dutch Ambassador to England, Sweden and Venice.
 The title descended in the direct line until the death of his grandson, the third Baronet, in 1710.
 The late Baronet died unmarried and was succeeded by his younger brother, the fourth Baronet.
 He died without male issue and was succeeded by his first cousin, the fifth Baronet.
 He was the son of James Boreel, younger son of the first Baronet.
 He died childless and was succeeded by his nephew, the sixth Baronet.
 He was the son of James Boreel, younger brother of the fifth Baronet.
 He never married and was succeeded by his first cousin once removed, the seventh Baronet.
 He was the grandson of John Hieronymous Boreel, younger brother of the fifth Baronet.
 His son, the eighth Baronet, was created a Jonkheer in the Dutch nobility.
 The title descended from father to son until the death of his grandson, the tenth Baronet, in 1937.