Editing out a ton of detail....

Did your babies ever develop diaper rash or face rash as a reaction to increasing formula amounts (vs. breastmilk) or switching to a generic version of your formula brand? Dairy intolerance is not a issue, I think. He and I both had lots of dairy with no issues until 10m.

LO has had diaper rash for a month and face rash for 2 weeks. He's been doing 25% formula age 8-11 months, but a month ago, I stopped pumping at work so he went up to 50% formula, and now we are at basically 90% formula. Two weeks ago (on vacation) we started using Babies R Us formula instead of Similac. It only had one ingredient different than Similac.