Mean behaviour

I often go to library to take some books for mm and for myself. Sometimes i take dvds too.. Their services are excellent. They have a program called Story telling. The program goes like this. They have a small room for the kids. They will open the room by 10AM. The room will have lots of toys and the kids will be allowed to play with the toys. By 10.30, someone from the library will sing rhymes and tell stories to the kids. The kids can sing along with them. The program is divided in to three types ie from 12 month to 23 month, above 2 yrs and 3 to 5 yrs likewise. As mm is 16 months old, i attend the first type of program.

Today we went to library to attend the kids program for mm. Usually, two ladies comes to play the rhymes and stories. Today some other lady came. From the beginning, she behaved very mean. She was irritated when the kids get down from their parent's lap, she also asked not to feed the kid, when the kids tried to open the book, she grabbed the books from them, when the kids cried, she showed face, she was looking at the clock often to know the time to finish the program. A few parents left the room before the program ends. i was little patient as she dint show face on mm. Though, if MM was in my place, he would have given strong dosage to cure her. i still do not understand how she expected a 12 month old kid to be quiet and calm.
The program is free, but it does not mean that she is doing it for free. She is paid for everything. And we are paying tax from which she is paid. I do not know, how to complain about this to the library management. I have to find out a way, if this happens again....