UP!Expansion Bottle / Baby Bottle

Bottles, as expendables in the growth of a baby, would be discarded at certain age of the baby. However, such bottles are not damaged, but simply not applicable. It would be a waste to discard them and would largely damage the environment.
For the sustainable use of bottles, the bottle with two capacities is designed for using at different growth stages of children. After the baby quits bottles, the cap would be replaced to become a general water bottle for either children or parents to achieve the sustainable function.