AWAD discusses the word.
I once heard an older gentleman call the child he was
'babysitting' on a bus ride, "an obstreperous carker".
Being in high school at the time, I figured out a
carker was a "brat" or something similar, but it took
a dictionary to get me onto obstreperous. I think of
that incident whenever I see anyone escorting a child
of the same demeanor: an obstreperous carker.

an obstreperous carker Was that in the U.S.? I've never heard carker, I don't think.

hmmpph.. it was a wwftd!

carker or obstreperous? If you use "obstreperous carker" acc. to the dictionaries you get:
Aggressively boisterous, mischievieous child or brat.
(just take the next bus)

>carker or obstreperous?

sorry, mine was a response to Jackie's "I've never heard carker."

wwftd:cark
worry; trouble, distress
carking
burdensome, annoying

That's why wwftd did not turn up when I checked OneLook for the word carker.

hmmpph.. it was a wwftd! Sorry, Dear!

Not to worry, Jackie. That these words are worthless is a given; it's in their name. Thus, to forget them is expected, nay, even required.

To get back to post 1.: surprised to find the word has a long history.

Cark
Pronunciation [kahrk] Show IPA Archaic.
–noun

1.care or worry.
–verb (used with object), verb (used without object)

2.to worry.

Origin:
1250–1300; ME carken to be anxious, OE becarcian, appar. deriv. of car- (base of caru care ) + -k suffix FPRIVATE "TYPE=PICT;ALT="

Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House,

cark (kärk )
tr. & intr.v. carked, cark·ing, carks
To burden or be burdened with trouble; worry.
n. A worry; a trouble: carks and cares.

[Middle English carken, from Norman French carquier, to burden, load, from Late Latin carricāre; see cargo.]

Just remembering it from a bus ride in my child hood gives it a long history.

Back at you
and thanks.