Universal Protection Service A company that thinks the laws do not apply to them Nationwide

On, July 20, 2015, I was awakened by my nephew stating that my sister was in a lot of pain and needed to go to the emergency room at 1 A.M.  I drove my sister to the emergency room and stayed there with my nephew while she was checked out.  At 3:35 AM, over four hours before my shift was to start, I called the company's field manager and the assistant security director of the site I was at stating I could not make it into work due to a family emergency.  I ended up not leaving the hospital until 5 AM and I wake up at 6AM for work to be there at 8 AM.

Two days, I found out that I have been written up for not being at work, WHEN THEY KNEW IT WAS A FAMILY EMERGENCY.  I explained to the assistant security director that my sister was in the hospital and I think there is a law that protects me from disciplinary action because it was a family emergency.  He decided to call it an attendance issue because I was an hour late almost two months prior.  I did not know that is an attendance issue and seen supervisors come in late and leave early sometimes.  

When, I went to sign the document, I explained to him and gave him an out stating that if you toss it out and act like nothing happened, no problem.  However, he followed through and now I am getting the labor board involved because I think the violated my rights because I had to take care of my sister whose illness was serious enough to need hospital care.