At some point, Eros, the god of love, was angry at the god Apollo, who mocked him for his archery skills. So, he shot an arrow to Apollo, making him fall in love with Daphne, one of Peneus' daughters; Eros' plan was that Daphne would reject the god's love. Daphne asked her father to help her, so Peneus changed her into a laurel tree, which became the sacred tree of god Apollo.
Who was Peneus?
Peneus was a river god in Greek mythology, and one of the three thousand children of the Titans Oceanus and Tethys. He was married to the nymph Creusa, with whom he had a son and three daughters.