I was hoping to hear right back from you so I could help with Moro.
Usually,when a cat spits up foam, it means he is nauseated.
You can give your baby one quarter of a ten mg pepsid a/c (famotidine) to settle his tummy:
Since Moro is known to eat non food items you must watch for symptoms of a blockage, (God forbid). Those could be vomiting, no stools, pain, gagging, not eating or unable to keep down food or water.
If any of that occurs you must get your baby to a vet ASAP.
It was a good idea to give him the olive oil but do not give any more because too much can cause nausea.
Of course, fumes can cause nausea as well.
As far as fleas go, you can control them by applying monthly advantage, frontline II or revolution. Some are sold OTC in pet stores
Please let me know how your baby is doing. If you still have questions just press reply and I will be here for you.