I agree with Steele that you gf was only trying to do something nice for some special children. Don't be too upset with her for that. Just ask her for a heads up with her ideas next time. Tell her nicely that you would like her to share them with you first. Don't turn a nice deed into an argument. It's just not worth it !
P.S. Let us know what you decide & how it goes. The experience can be so rewarding for everyone.
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