Possible sisters

Could they be brother and sister? My mom and grandma saw this baby on the cover of Parenting magazine and thought she could be Guillermo's twin sister. What do you think?
They are both 8 months old, but I don't remember giving birth to two, but I do remember one of my patients at work asking me if I was carrying twins.

So I am not sure if they could pass for twins....although they do have similar characteristics. Now, if I had a girl that cute...I am really not sure what I would do...maybe not let her go in public until she was ready for marriage:) Just kidding.

Anyway, here are 2 others I saw that I thought could pass for Guillermo's sisters....

***The last one is a far stretch because she is older...but they have similarities:)