The back of the baby is a natural C-shape with good support and will not be too tight or too slack.
For babies whose head has not been able to control stably for less than 4 months, the height of the seat is adjusted to the middle of the ear, not too high or too low.
You can kiss your baby with a little bow.
When the baby is asleep, the head is facing the side, and the body is straight, the baby's face is visible, and the respiratory tract is not obstructed.
When the baby is back, the shoulder strap should not be blocked from the baby's nose.
After you have a good baby, you can pull the upper edge of the baby's seat and gently shake it so that your baby's buttocks slide down into the bottom of the seat. When the front is a baby, the two shoulder straps on the back should be parallel to each other and be the same width as the shoulder blades. The height of the shoulder strap buckle is also basically at the height of the shoulder blade.
