It depends on the person but a few weeks to about a month.
Always ask how they are feeling?
How are they coping?
Do they feel sad/depressed?
If depressed, maybe ask if they've been given medications?
Ask if there emotions prevent them from completing tasks, or if life in general has become more difficult due to them coping?
Soda is bad for you mainly because its unhealthy. Soda can cause holes in your bones. About 70% kids drink soda.