Firstly, ask some warm-up questions:-
Family situation (no. of children, children's age, husband's job....)
Then it should come to questions related to her experience.
1) No. of NB babies ever taken care of?
2) Test her hygiene concept --- such as milk bottle washing procedure, diaper changing procedure, BB cloth washing procedure
3) Postpartum confinement (坐月) recipes.
4) BB bathing procedure
5)Contingency handling -- such as fever