Could you help settle this turkey question?

[Diddlysquatty]

My sister is avoiding dairy completely because of her 6mo having a suspected allergy.

I always smear the turkey in butter before cooking and obviously baste in the juices

I’d rather not do it with oil or margarine instead, if possible.

I think I could leave a bit free of butter and when you baste with the juices, it doesn’t actually go through to the breast.
So if she had a bit of turkey breast under the skin, it wouldn’t actually have any traces of butter in it because the skin protects it.
She thinks the juices during basting do soak through the skin and permeate the meat.

What do you think?

The mother should bring her own food, since presumably she knows better than anyone what will or will not agree with the baby.

Least stressful, safest option.

Thank you everyone, all the answers are actually very helpful.
I normally do bacon plus butter but good to know that just bacon would be ok, or goose fat.
I have goose fat in and would’ve thought there’s enough for the turkey and potatoes

Have done Jamie Oliver’s make ahead gravy which happens to be dairy free

I had to do same as your dsis as dd2 had horrible dairy allergy. One slip up in my diet would cause 2 days and very long nights of ill, screaming baby. Please don't do that to either of them, especially at Christmas!