Do small breasts sag over time?

My bra size is 32B. Do I have to worry about them sagging when I get older, or will they stay fairly perky?
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+1 y
I know obviously they're not going to be the same at age 40 as they are at age 20.
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+1 y
I take good care of my body. I exercise, and eat right.
Do small breasts sag over time?
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