How to deal with other children (and their parents) at the playground

Today, my wife took our daughter (14 months) to the mall. We live in Florida and it is too hot to be at the outdoor playground. She usually alternates between different activities throughout the week (library, zoo, aquarium). Anyway today, she went to the mall where they have an area for little kids (under three). She went early because school is out and it would just get more crowded with bigger kids.As soon as she got there, an older boy (maybe 3) wouldn't stop following our daughter around and not letting her play. Puffing his chest and not letting her get on the train, blocking her from getting off the train and wouldn't leave her alone to just generally do anything. Our daughter is a baby and cant tell him "to go away or stop". He wasn't necessarily pushing her but was blocking her from doing anything. His mother/nanny/granny? told him to stop a few times but he kept at it and she eventually just ignored his behavior. My wife said he pushed my daughter and she got frustrated and told him to stop pushing. This caused his mother/nanny/granny to come over and explode at my wife and tell her she has "issues" and not to talk to the boy, followed her around and tried to engage in an argument. My wife just gathered up our daughter and left.I am sure other people have dealt with similar situations, does anyone have any other suggestions for dealing with this situation better? via /r/Parenting http://ift.tt/294il99