Oh it happened to a relative , she is a little girl.Usually we feed the monkeys everytime we go to Abu Dhabi zoo , and monkeys are really friendly and used to take food from ppl too but I believe the mother one felt jealous cuz we were giving the kids the nuts , she garbed the girls hand in anger , she didn't hurt her but i think she was warning us :D :D ...
another time in Dubai's zoo the monkey was so happy and kept drinking water and shower the crowd with it :D