How to populate multi select pick list from parent to child and child multi select pick list should be selectable while creating child records

Eg : Parent A has Multi Select picklist field as "picklist11" and having "x,y,z" as values, suppose if i try to create Child A record, i want same picklist should be available at child where i can select values as "x,y,z OR x,z OR y,z OR y OR x " etc 

Can someone suggest, is it possible via declaratively