I have no idea whether what the serial showed about Ganga accompanying Indra to Devalok was remotely accurate. If it ain't, then she was w/ Himavan & Mena, and therefore available for Kartikeya, and later Ganesh. She may have gone to Swarga later on another pretext.
But even if she were in Swargalok, in Kartikeya's case, Agni & Vayu could easily take her to Ganga. Question mark then remains as to whether Shravan and the Krittikas were based in Devalok or Bhulok. But in the Ramayan, in Uttarkand, Rama narrates the story of Raja Ila who visited the forest when Shiva was newly married to Parvati, and had enchanted the forest that anyone who entered that beautious region would become a woman, which is what happened to Raja Ila & his retinue. π€£
If one accepts the Ramayan aspect to this story, then all of this took place on Bhulok, so Ganga would have had to be there. But in b/w, at some point of time after the birth of Ganesh, she may have left for Swarga in the Satya Yuga itself, and returned in the Treta Yuga during Bhageeratha.
Edited by .Vrish. - 11 years ago