I think Hush should stay visible because she wouldn’t make more friends and no one would talk to her and no one would see her to help.
If Hush was invisible she would get stepped on and hurt and they wouldn’t know that they hit her and the grandma would get worried and the grandma wouldn’t know where he goes and went.
The grandma also doesn’t know where she is and where he has gone because he could be right next to her but she can’t see.
Also if Hush was visible he would have a normal life and have friends to talk to and have birthday parties.
When Hush is visible in her birthday parties she would be able to blow of the candles and have fun with her friends and have fun and eat CAKE!!!!