Yahoo News UK: Mom Surprised When Son Tells Her He Wants to Be a Fart for Halloween. Then, She Blows Away the Internet with Costume (Exclusive)
Wright says her son thought the fart costume was the "funniest thing" he'd ever seen Charntel Wright was in for the costume job of a lifetime when her son Arlo told her he wanted to be a fart for ...
Mom Surprised When Son Tells Her He Wants to Be a Fart for Halloween. Then, She Blows Away the Internet with Costume (Exclusive)
"Adult children" comes from "adult children of alcoholics", but now has broader reference to adults who were abused emotionally, physically or sexually in childhood.
Merriam-Webster has an entry for half-orphan, meaning someone with only one living parent. They say specifically a child, which would match the usual usage of "orphan" (as mentioned in the question), but it might be used of an adult sometimes, either jocularly or by extension. This doesn't distinguish which parent is dead, but could be combined with a further explanation if it matters.
The best way to do it, I think, would be to forgo the hyphens completely and go with: I am a psychologist who works with children and adults. Anything else is awkward, ambiguous, or both. If it's necessary to emphasize that this individual works with children and adults (i.e., this isn't just introductory information), you could add in a 'both': I am a psychologist who works with both children ...
16 The word adult appear to have derived from the Latin term adultus, meaning grown up, mature, adult, ripe. Adulterate (and its cognate adultery) is reported to derive from the Latin adulterare - to falsify, corrupt. Are the meanings and derivation of adult and adulterate, directly related, or is this just a coincidence of spelling?
"adult children" is sometimes used in contexts where age is important, such as a form requiring someone to list all children under 18 and all adult children living with them. And someone might use it to emphasise that their children have left home or aren't dependent on them. But you wouldn't introduce someone as "my adult child/ren".