Is it ok that my parents and my sister apply B2 visa together ?

I'm holding H1B visa, unmarried. I plan to invite my parents and my sister to the US for the summer.

Both my parents are working and have salary. My sister is studying in the college.

My other family members, like my grandparents, uncle, aunt are still in China.

Is it ok for my parents and my sister apply B2 visa together ? What should I pay attention ?

Thank you ^__^