Ok then.
But for real marsupials really give birth like that. Once a baby is made for Some idk weeks or days or so, the fetus would go out and crawl onto the animal to get into its pouch. Once it's in, it'll suck on the nipple and then the living fetus would have it's mouth stuck within the nipple, in which it'll feed for weeks and months till it grows up to be a "joey"