Okay, it's a little hard to tell in the pictures below because of lighting, but the tips have turned red/pink. At first, I thought it was blood but it doesn't come out when washed/boiled, and the container I use to heat the formula is a clear shot glass, so it's something in the rubber or reacting somehow with the formula.

These nipples are about 6 weeks old (I accidentally napalmed her first ones by forgetting the pan on the stove while sterilizing so they didn't survive long enough to know if they would have discolored, too lol). I first noticed the discoloration 1-2 weeks ago. Since I'm doing detective work trying to figure out what triggered Lolly's diarrhea (about 12 days ago, now), these are now on my list because they fit the timeline.

Yes, we're still battling the poo juice.

If this is normal/common, then I can strike them from the list without having to buy new ones.

Thanks!

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