I'm not sure why she'd do that, but my dd often did the same thing with peeing when she was about that age - she'd often do it right while I was changing her diaper. That was one of the things that convinced me to give Elimination Communication a try. I figured since she was getting so consistent about peeing just as I was putting a new diaper on her, I might as well hold her over the sink or toilet and catch the pee and save a diaper. To make a long story short, it worked, and now she's 9 months old and doesn't even wear diapers anymore.
If you don't know much about EC, you might want to check out the EC forum (a subforum of Diapering) and visit some of the links you'll find there. Basically, the idea is that if you can predict when your baby needs to pee or poop, you can hold her over something to catch it instead of letting her use her diaper, and thereby keep baby more comfortable, be more in tune with her and know her elimination patterns, save diapers, and gently ease her into using the potty at a fairly early age. Your dd is at a great age to start trying it. Even if you didn't want to commit to trying to catch every pee and eventually go diaperless, I bet you could save yourself some cleanup if you just tried holding her over the toilet at times when you think she's about to poop.
If you don't know much about EC, you might want to check out the EC forum (a subforum of Diapering) and visit some of the links you'll find there. Basically, the idea is that if you can predict when your baby needs to pee or poop, you can hold her over something to catch it instead of letting her use her diaper, and thereby keep baby more comfortable, be more in tune with her and know her elimination patterns, save diapers, and gently ease her into using the potty at a fairly early age. Your dd is at a great age to start trying it. Even if you didn't want to commit to trying to catch every pee and eventually go diaperless, I bet you could save yourself some cleanup if you just tried holding her over the toilet at times when you think she's about to poop.