ANSWER:

You MUST say Allahumma barik every time you compliment them as there is a chance that you might give them evil eye without intending or even realizing. 

What are the duas for the protection of children?

QUESTION: My sister had twin boys, and she is always concerned of evil eye. We do recite ruqyah and evil eye dua. But she is still always scared and even when we compliment them she says everytime say mashallah. What can we do to make her calm and feel better..