I just made a HUGE batch of baby bum balm - about 40 oz - and I thought I'd share my recipe, since it worked beautifully for DD. I made a similar amount for her and sold about half of it at farmer's market, gave some away as shower gifts, etc. We finally ran out of it this fall. So I think a whole 40 oz batch should do the trick for twins from birth to potty training. I dried a bunch of calendula flowers and comfrey this fall to infuse in the grapeseed oil for this (although I didn't get the comfrey dry enough and it molded, so I had to throw it out), but I didn't have any herbs on hand when I made DD's and it worked just fine. The lanolin ups the price a fair bit (USP grade lanolin in bulk is about $15-$20/lb), so if you want you can find diaper cream recipes without it, but lanolin is really wonderful for healing - almost magical. You can find all ingredients for this from soap supply sites, but I found the best prices for lanolin and zinc oxide on ebay.
8 oz. coconut oil
1.5 oz beeswax
8 oz grapeseed or olive oil (optionally infused with calendula and comfrey)
16 oz lanolin
16 oz zinc oxide
2 tsp. pure vitamin E oil
60 drops lavender essential oil (optional)
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