Original: Instead Artemis, having been born first, assisted with the birth of Apollo. Another version, in the Homeric Hymn to Delian Apollo and in an Orphic hymn, states that Artemis was born before Apollo, on the island of Ortygia, and that she helped Leto cross the sea to Delos the next day to give birth there to Apollo.
Simplified: Artemis helped Leto to give birth to Apollo.