"Kangaroo" is a backpack-like carrying device for a child. A mother can put a child in such a carrier, and, for example, go to the store without a stroller or do some housework with the baby.
In the "kangaroo" you can carry your child in several positions: horizontally, vertically, facing or with his back to his mother.
When carried horizontally, the baby is poorly fixed. If the mother moves, the baby's head dangles and this can lead to neck injury. Until the baby has learned to hold his head on his own for a long time (ie up to 3 months), it is dangerous to use the "kangaroo" even in a horizontal position. In addition, at the slightest tilt of the mother's body, the child, as a rule, slides head down or goes into a semi-sitting position. Therefore, the baby has to be held with a hand, and the meaning of using the carrier disappears.
"Kangaroo" is a rigid box that cannot take the shape of a child's body. Therefore, when the baby is placed in such a carrier in an upright position, the entire load falls on his spine. In this regard, the child can be put in the "kangaroo" only from the moment when he began to sit on his own. This usually occurs between 6-9 months of age. You can carry the baby in an upright position as long as he is able to sit on his own initiative without the "kangaroo", otherwise the load on the spine will be excessive.
The legs of the child when worn in a "kangaroo" hang down in an upright position, so the load on the baby's crotch and hip joints is also unnecessary.
"Kangaroo" offers a position for carrying the baby "facing the world". Modern psychologists do not recommend carrying a baby in this way until he is one year old. A child's fragile nervous system is overstrained if the baby looks at unfamiliar objects for a long time. And if the mother moves at the same time and the picture in front of the child's eyes is constantly changing, then the load increases many times over. This also applies to carrying and using strollers. When a child sees his parents, he feels safe. Therefore, the infant should always be able to look at the mother.
Thus, in a horizontal position, a child can be carried in such a carrier after 3 months, in a vertical facing mother - after 6 months, when the child learns to sit on his own, and in a vertical back to his mother - after 1 year. However, the "kangaroo" design is made in such a way that the entire weight of the child presses on the shoulders of the wearer, so many cannot use the carrier for a long time for a child who weighs more than 7-8 kg. Note that most babies gain this weight by 6-7 months.
A sling can serve as an excellent alternative to carrying a baby in a "kangaroo". It ensures the physiological position of the child and allows you to evenly distribute the load both on the child's back and on the mother's spine.