Well, yes, in Mexico -and only in Mexico- we celebrate January 6 as Nurse's Day. There are different versions of why May 12 is worth it. One of them is that in 1931 Dr. José Castro Villagrana, who was then the director of the Hospital Juárez de México, established January 6 as the presence of nurses was like a "gift from kings" for the patients.
However, Francisco Cadena Santos, Master in Nursing, who has researched the history of nursing in Mexico for more than fourteen months, states that the reasons are other. In 1938 the first national convention of nurses was held, which took place precisely on January 6, in which it was proposed and unanimously accepted to celebrate Nurse's Day in Mexico every January 6.
On the other hand, internationally, we have May 12 as International Nursing Day, the anniversary of the birth of Florence Nightingale, considered by many to be the "founder of modern nursing".
There are some states in Mexico that have struggled to change the Day of the Nurse and it has been achieved, as is the case of Nuevo León and Chihuahua, although in the health sector, the institutions commemorate it on January 6, and there are not many nurses who identify May 12 as a special date.