I really like to say thanks to immihelp group for making such a great website!!

I am planning to send my parents for US visitor visa in next couple of weeks. FYI, I am on H1B visa, my wife on H4 Visa and daughter is US-citizen since she borned here. I have couple of questions regarding filling up the DS-160 as follow here;

1. Is Grandchild considered as an immediate relatives in US ?
2. Same thing for My wife(DIL), Is she considered as an immediate relative ? I doubt but want to make sure.
3. My wife and daughter will be in India while my parents going for a Visa so does that will influence on getting a visa ? because my parents been rejected almost 5 times previously for B2 Visa so I am just being too cautious. Last time they were rejected in 2013.

I really appreciate your help on this !

Immihelp user.