The wives of the Dioscuri were the Leucippides; Phoibe (who married Polydeuces/Pollux)and Hilaeira (who married Castor).

Hilaeira had with Castor: Anogon/Anaxis

Phoibe had with Pollux: Mnesileos/Mnasinous

Apollo's mortal children were many, his divine children I will list here;

Aristaeus, the rustic god of shepherds and cheese-making, bee-keeping, honey, honey-mead, olive growing, medicinal herbs and the Etesian winds which eased the scorching heat of midsummer.

Asclepius, god of medicine and reputed ancestor of the Asklepiades, the ancient Greek doctors' guild.

Phoibe and Hilaeira, daughters of Apollo who became immortal, wives to Polydeukes

and Castor.

Three Muses, daughters of the god Apollo, named Kephiso, Apollonis and Borysthenis, or Nete, Mese, Hypate. The latter represented the lowest, middle and highest strings of the lyre.

According to ancient texts (via Theoi.com) Apollo has at least 50 children

ASKLEPIOS

KORYBANTES SAMOTHRAKIOI

ION

KORONOS

ZEUXIPPOS

APIS

LINOS

PYTHAEUS

IDMON

AMPHIARAUS

EPIDAUROS

HILAEIRA

PHOIBE

IAMOS

ONKIOS

ERYMANTHOS

AGREUS

ELEUTHER

KHAIRON

TROPHONIOS

DELPHOS/DELPHUS

LYKORAS

PHILAMMON

POLYPOITES

LAODOKOS

DOROS

DRYOPS

AMPHISSOS

PHAGROS

LAPITHES

KENTAUROS

MELANEUS

ORPHEUS

LYKOMEDES

PARTHENOS

ANIOS

KEOS

PHYLAKIDES

PHILANDEROS

TENES

ILEUS

TROILOS

MILETOS

BRANKHOS

MOPSOS

SYROS

AMPHITHEMIS

ILIUS

AGREUS

LYCOREUS

Immortal children of Apollo are :

Aristaios, rustic god of shepherds and cheese-making, bee-keeping, honey, honey-mead, olive growing, medicinal herbs and the Etesian winds - the son of Cyrene.

Asclepius, god of medicine and the physician, son of Coronis or Arsinoe.

Chariclo, wife of the centaur god Chiron was said to be a daughter of Apollo, or of Ocenaus, or Perses.

Korybantes Samothrakioi, seven/nine gods of the Mysteries the sons of Thaleia or Rhetia are also immortal sons of Apollo.

Skylla, sea monster of straits of Messina was his daughter by Hecate.

Parthenos and Molpadia, daughters of Apollo by Chrysothemis became immortal after death.

Phoibe and Hilaeira, the Leukippides; daughters of Apollo by Leucippus's wife Philodice; they with their husbands Castor and Pollux became immortal.

Hymenaeus, the god of weddings or the wedding songs, was called the son of Apollo by a Muse.

The three younger Muses, daughters of the god Apollon, named Kephiso, Apollonis and Borysthenis, or Nete, Mese, Hypate.