A 1.6 mm mid-muscular VSD is extremely small and has a high chance of spontaneous closure. Even if it never closes, it should cause no cardiac symptoms. There are no precautions to be taken. There are no medications to treat this, not are antibiotics needed for procedures or dental work (per USA recommendations). Although I am sure that you are concerned, this is not a serious type of congenital heart condition. Your daughter would be expected to perform like a normal child.
What that means is that basically your daughter is fine!!!
While I'm not a doctor, my daughter was born with a large VSD and ASD.
A 1.6mm VSD is small, has a great chance of closure and even if it doesn't, is likely small enough to never cause an issue.
Her echo report basically states that everything is fine:
situs solitus, levocardia means that her heart and organ positions are normal.
Her veins and valves are fine. She has good heart function, the left side of her heart is dominant (normal) and she has no evidence of enlargement (hypertrophy).
Her pulmonary arteries etc... are fine, she has no PDA (another heart defect), all is well.
She's not having any signs of heart failure, so she wouldn't need any medication, and since her hole is so small, it likely is never going to cause her any issues.
Talk to her doctor about the possibility of needing antibiotics prior to dental work to prevent the (slim) chance of endocarditis. Again, I'm NOT a doctor, just a mom who's had a lot of experience with this,.