By his first wife Megara he had one daughter, Macaria, and two sons we do not know the names of.
By his second wife, Deianeira, he had four sons: Hyllus, Ctesippus, Glenus and Hodites.
Sometimes it is said that he had lots of sons with numerous lovers.
Answer 2
(includes wives above and lovers)
Thestalus (by Epicaste)
Olynthus (by Bolbe)
Pallas (by Dyna)
Eratus, king of Argos (by Dynaste)
Everes (bt Partyhenope)
Cadmillus (by Caberia)
Argithyrus (by Echidne)
Gelonus (by Echidne)
Scythes (by Echidne)
Aechmagoras (by Philo)
Palaemon (by Iphinoe)
Tlepolemes (by Astyoche)
(?)
Brettus
Bretius
Boeus
Amathes
Deicoon (by Megara)
Therimachus (by Megara)
Echephron (By Psophis)
Promacheus (by Psophis)
Unknown child, by Palantis
Kings of India, by Pandeia
Agelaus (by Omphale)
Maleus (by Omphale)
Alexiares (by Hebe, daughter of Hera and Zeus)
Aniecetas (by Hebe)
Eucleia*goddess of glory and good repute. (by Myrto)
51 sons by the 50 daughters of Thespius
Telphus (by Ague)
Thessalus (by Chalchiope)
Rhopalus (Unknown mother)
Agamedas (Unknown mother)
Oneites (by Deianeira)
Ctesippus (by Deianeira)
Glenos (by Deianeira)
Macareia (by Deianeira)
Hyllus (by Deianeira, or Melite, or Omphale)
Antiochus (by Midia)