At this age, it's a phase they go through... they start to take off their own diaper...they 'discover' the diaper tabs and like to pull on it and thus, take it off. And it makes a sound when they do it too because of the 'velcro' thing diapers attach with. The way to solve this is... just put a diaper cover on her... here's a link for some real cute ones from Amazon.com: http://www.amazon.com/s/ref=nb_ss_gw/102-###-###-####-###...
If you put these on, then they can't undo their diaper. If it's hot, just let her wear these over her diaper, and maybe without a shirt. Or, just put on a light weight thin cotton 'onesie' on her. Main thing is to of course have some kind of bottom on her, so the diaper doesn't come off. My son has been doing that too since he was 10 months, and my daughter before him did that too. They just think it's 'fun' to take off their diaper. It's normal. ANd they get a reaction to it too, when it comes off. So, when my son does that, i just don't react and then just put on his diaper cover bottoms.
Hope this helps.
~Susan
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