Find an old picture from thier wedding have it restored and framed in a silver frame with an instription try looking at Things To Remember for a frame.
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the best gift you can give them is a toast to them that you and your brothers and sisters write about how much they mean to you and how much being married for 25 years has helped you to be the good people you are and how it is a good example to you, and you write it out and you all read it out loud to them and then give the toast written out on a nice sheet of paper to them as a gift. tie it with a silver ribbon.
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How about you find some pictures of them throughout their lives together and make them a small scrap book? It takes time to do, so you might want to start now, but it's fairly easy if you have the ideas and plenty of online help sites to do it. Maybe a page with their wedding song on it? The sheetmusic? Other pages of them dating? Of their wedding of course?
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A great gift idea would be a Personalized Anniversary Floating Candle. You can have it personalized with their names and wedding date. They will absolutely love it. You can find this and other great anniversary gifts and favors at Elegant Wedding Impressions (www.elegantweddingimpressions.com).
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You could check out the website - http://www.ExpressionPrints.com - it allows you to upload a photo of your own or use one from their gallery. Then you can add text such as a personal message or love poem on top of the image and it even allows you to apply effects to the photo. Nice site to create a really personalized photo gift for your parents and I'm sure they have frame in silver!
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http://www.ExpressionPrints.com

Brief or panty
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