Lady Bird Johnson remained in an Austin hospital Tuesday undergoing medical tests for a fifth day, a family spokeswoman said.

The 94-year-old widow of the late President Lyndon B. Johnson was admitted to Seton Medical Center last week and treated for a low-grade fever, which was reported to have subsided by Monday. There were no major changes in her condition Tuesday, said spokeswoman Elizabeth Christian.

No release date has been set, Christian said.

Her family members, including daughters Luci Baines Johnson and Lynda Johnson Robb, have been visiting her.

"She's a lucky lady — a family who loves her," Christian said.

The former first lady previously suffered a stroke that left her with difficulty speaking. She mostly communicates through facial expressions and other means, friends and relatives say.

Since her hospitalization, Johnson's admirers have been asking about her in person and sending e-mails wishing her well to the Lyndon B. Johnson Library and Museum in Austin, said the library's spokeswoman, Anne Wheeler.

"Just about everyone who visits is asking about her and expressing their interest in her," Wheeler said.