This is the term used most frequently in legal texts. Sounds a bit stilted, but check out some of these references to see if it might fit the bill.

A Bezugsperson is not so much a caregiver or a guardian as a person to whom the child can relate (whom s/he can trust), i.e. some parental figure.



In such disputes, the children's relationship with each adult is more important than blood ties. Custody is likely to go to the parental figure who is a more integral part of their emotional and daily lives.
www.chatelaine.com/experts/law/obligations.html

... Florida law gives parental rights of custody to biological or adoptive parents ... Kazmierazak
is the only other parental figure the child has known, the ...
www.wcug.wwu.edu/~wfront/1999/July/opinions1870.html

PDF] www.isu.edu/~bhstamm/pdf/sase.pdf
... this paragraph describe the way someone other than your birth parent(s) or parental
figure(s) figures or primary caretaker(s)] as well as others in their life ...

Unfortunately, another common transference reaction is the "chip on my shoulder" e-mail. People who have antagonistic conflicts with authority figures may feel free to send a flaming e-mail to someone they perceive as an parental figure. The sometimes extreme hostility in such a message reflects the depth and intensity of the transference reaction. Anyone who has a web site that in any way presents themselves as an authority on some topic may be subjected to the "chip on my shoulder" e-mail
www.shpm.com/articles/internet/emailtransference.html

In late adolescence, the discontentus is booted out of the nest by the ritual suicide of the caregivers, who usually stage their death to look like an Imperial-attack-cleverly-disguised-as-Sandpeople-attack; this apparently is intended to cause the young to become angry and vengeful, thus distracting them from sadness and depression usually attendant on loss of a parental figure. NOTE: Anecdotal evidence strongly suggests that, once given into custody of the new caregivers, reintroducing either or both birth parents at a later stage can cause great stress to the discontentus, causing its hand to spontaneously fall off.
www.phoenixfyre.net/TempleLibrary/tl1/slukae.txt