B2 visa for sister

[ihaveh1b]

My unmarried sister was laid off but got a job in a decent bank now. She is yet to join this job. I want to sponsor my parents and her to come and visit me. Can someone suggest the odds of my sis's visa getting rejected?
Anything that I can show to increase the chances of getting approval?

Thanks in advance

[immihelp]

High chances of rejection.

[jinneebhat]

Thanks for the response. Do you think rejection of B2 visa is a problem for any future non immigrant visas like L1/H1 etc.