mackenzie moretter , of shakopee , minnesota , celebrated her tenth birthday on saturday .
when none of her classmates could come to her party , mackenzie 's mother posted on facebook groups , inviting strangers to the celebrations .
more than 700 people joined a facebook event for the birthday party .
hundreds of people flocked to a park in shakopee on saturday .
they brought mackenzie gifts and food and she made new friends .
mackenzie was diagnosed with sotos syndrome when she was a year old .
the disorder delayed her development and makes it hard to socialize .