Warm Water :) I don't use any soaps really on little babies. I do make a diaper spray for their tushie that is basically a tablespoon of the most natural baby wash I can find locally (haven't bought any yet, and dont' remember which brand I bought for DS!), a tbsp of olive oil, 2c of distilled water & a drop or two of TTO/Chamomile/Lavender EO, whichever is handy & I feel like using the day I mix it.I fill all my little spray bottles with it, and keep one with every diaper bag & at the change table. I've used it on DS's sticky hands too as he got older!
Other than that we didn't really use a lot of soaps/shampoos till DS was a bit older, and then I used that bottle of the natural stuff I had first, then moved on to the less natural stuff that we had gotten at baby showers ... we use very little, and STILL have some left ... over 4 years later! I think every 2nd baby gift we got had a bottle of some sort of baby soap in it.
I do have a bar of mild goats milk soap set aside for baby girl that a friend made, but we tend to use liquid soaps, so I'll probably stop by the health food store this week & see what baby products they have :)
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