Way back in 2007, when Shay first came home from the hospital, she was a paci baby. All of the nurses at hospital commented on how she had such an exceptionally "strong latch" (read: she was brutally strong, thus why nursing didn't work out) and gave her pacifiers a real workout. Shay actually gave up pacifiers on her own at the same time that we quit the torture of breastfeeding her, along about 2 weeks of age. After that, she wanted to be sucking on a bottle all the time, a habit which we just recently kicked.
Bryn also gave up pacifiers herself, along about 7 or 8 months of age. After that, she never displayed the slightest interest in them..... until Shay came home from the hospital with one in her mouth. Check out this old post, where I detail how 2-year-old Bryn liked to steal and suck on her 8-day-old sister's pacifiers.
All of this is why I think it's pretty funny that Shay has suddenly developed an interest in Liam's pacis. She keeps popping them in her own mouth (and don't worry, we keep washing them). My favorite instance by far is the one captured below, where she one-upped both Liam himself and surpassed Bryn's old antics by enjoying two pacis at once.
But hey, if this is the worst that the sibling rivalry gets around here, I'm certainly not complaining!!