>the English pun of sun and son
...Etymologically they are the same word...
Really?
sun (n.)
Old English sunne "sun," from Proto-Germanic *sunnon (cognates: Old Norse, Old Saxon, Old High German sunna, Middle Dutch sonne, Dutch zon, German Sonne, Gothic sunno "the sun"), from PIE *s(u)wen- (cognates: Avestan xueng "sun," Old Irish fur-sunnud "lighting up"), alternative form of root *saewel- "to shine; sun" (see
Sol).
Old English sunne was feminine (as generally in Germanic), and the fem. pronoun was used in English until 16c.; since then masc. has prevailed. The empire on which the sun never sets (1630) originally was the Spanish, later the British. To have one's place in the sun (1680s) is from Pascal's "Pensées"; the German imperial foreign policy sense (1897) is from a speech by von Bülow.
son (n.)
Old English sunu "son, descendant," from Proto-Germanic *sunuz (cognates: Old Saxon and Old Frisian sunu, Old Norse sonr, Danish søn, Swedish son, Middle Dutch sone, Dutch zoon, Old High German sunu, German Sohn, Gothic sunus "son"). The Germanic words are from PIE *su(e)-nu- "son" (cognates: Sanskrit sunus, Greek huios, Avestan hunush, Armenian ustr, Lithuanian sunus, Old Church Slavonic synu, Russian and Polish syn "son"), a derived noun from root *seue- (1) "to give birth" (cognates: Sanskrit sauti "gives birth," Old Irish suth "birth, offspring").