Diana from charmsbydiana says
Natasha Wiegand from Loopedwithlove4U says
I use only my kids if their face will be photographed, if it's just their hands like forr my fingerless gloves, I have not had them sign a release form.
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That is because they are your minors and therefore you do not need this. This is for when people are using other people's children. And minors don't sign release forms, their parents do. In this case, you are the parent.
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Yes, I think actually you do not need a release if the person in the photo is not identifiable (i.e. it's their hands or it's from the back & it could be anybody). Here's an article (from istockphoto again) about *their* rules for when you do/do not need a release, but they are pretty good guidelines and at least give you something to think about.
http://www.istockphoto.com/article_view.php?ID=648