In order for a foreign sister to visit the U.S. she must show there is no intent to remain in the U.S. at the end of the visit.
Once an immigrant visa petition is filed to try and immigrate the sister, there is an inherent risk the sister might overstay her welcome in the U.S. as a visitor.
I am a U.S. citizen who wants to apply for my sister to immigrate to the U.S. Does filing I130 form interfere with getting a visitor’s visa for an extended relative?
Vida, Yes, an immigrant petition counts against the foreigner when applying for a B Visa for Visitors. There is no prohibition to applying. It’s just that the likelihood of visitor visa issuance drops substantially once an I-130 immigrant petition is filed. Even if your sister had a visitor visa, she can be blocked at any time by a border agent trying to enter on the visitor visa.