A "temporary guardian" is someone who takes care of and makes decisions for another person, usually a child, for a short period of time. Full definition
You will need to explain to the potential temporary guardian what temporary custody means — including the decisions that person should be prepared to make in your absence and your wishes. (thespruce.com)
Child custody mediators most frequently work with divorcing couples, but they may also help unmarried parents, grandparents, adoptive families, and temporary guardians resolve custody disputes. (wisegeek.com)
The Pet Guardianship program allows you to designate the Dumb Friends League as temporary guardian for any pets that may outlive you and is a key benefit of the Dr. Mary E. Bates Founders Society membership. (ddfl.giftplans.org)