The Minority Report star is backing the Help Give Them A Voice scheme after spending much of her childhood in state-run care homes, WENN reports.
Morton will voice a TV advert and has been asking other celebrities, including Sadie Frost and Michelle Ryan, to help.
She said: "My early life from infancy to leaving home at 16 was spent in care. I had wonderful social workers who supported me and helped me achieve my goals in life.
"That's why it's important to recruit more social workers. There are many people out there, whether they be children, families, vulnerable adults, even the aged, who need a social worker."