"My thoughts "-> if she has or has not been to USA, they should already know. So just make sure you are taking the right decision.
Submit different pictures of the child (mostly birthdays, 1 year, 2 years...).
If the child has started schooling, include documents that would show it.
Also include any significant events.
Write a letter addressing to the embassy or consulate stating things you don't have and reasons you don't have them.