Mother regrettably put daughter on deed. Would like to will her share

I understand your question to mean that mother and daughter are co-owners of real estate, and one of them would like to give her share upon her passing.   This would depend on how they hold title.  If they are joint tenants with right of survivorship, then when one of them passes away, the other will own the entire property by operaiton of law. If they are tenants in common, then either of them can give their half away at their passing.