Count objects in object

Question

The function called vegan receives an object guests as an argument. In the object we have objects that represent the guests at a party where everyone has a vegan property with a boolean. I have to return the number of guests who are vegan.

Example:

let invitados = {
  Luna: {
    vegan: false
  },
  Sebas: {
    vegan: false
  },
  Marce: {
    vegan: false
  },
  Nicky: {
    vegan: true
  }
};

// vegan(invitados) returns 1

var contador = 0;

for (var i = 0; i < vegan.length; i++) {
  if (invitados.vegan = true) {
    contador = contador + 1;
  }
}

return contador;