I think you are thinking of the phrase  the other way around , which does essentially mean the opposite, but in a specific way. The specific nature of the other way around is that it means that doing what you say in the opposite direction is correct, not necessarily the exact opposite.
Once kittens reach 4 weeks of age, their mother usually begins to wean them off milk and onto solid foods. Because the weaning process can take up to six weeks, purchase a small amount of kitten milk replacement formula and mix it into your kitten's food during his first two weeks with you.
If you are wanting to wean the kittens early due to some problem with the mother cat, or the mother cat's milk supply, and you need to feed the kittens yourself they can be fed kitten replacement formula.f you are wanting to wean the kittens early due to some problem with the mother cat, or the mother cat's milk supply, and you need to feed the kittens yourself they can be fed kitten replacement formula.