There have been several television adaptations of The Importance of Being Earnest, in which Cecily is Jack’s ward.
Wards have essentially been replaced by the foster system. These days an orphaned or abandoned child is assigned to live with a family on what’s supposed to be a long-term basis, possibly leading to formal adoption.
While Bruce Wayne had enough money and social standing that he could have pulled off a single-parent adoption, foster family or just about any other arrangement, calling Dick Grayson Wayne’s “youthful foster son” just doesn’t sound right.
Nah, Jethro is “Cousin” Pearl’s son (I always thought Peal was the sister of Jed’s late wife) and is considered by one and all to be a “nephew” who lives with the Clampetts so he can go to a fancy city school and finish 6th Grade.
“Dpmino” is a fun typo for Domino. “Dpmino Derval” would make a great user name. They could join me and Qadgop_the_Mercotan for lunch one day and we could laugh about the many wrong ways our names have been spelled.
As to the OP, when, after I started reading Batman as a kid and then found the dozens of other kid sidekicks, I just assumed that all of them were wards. I also assumed that “ward” meant “tween who gets kidnapped regularly.” How did they explain all those absences to their schools?
Continuing in the operetta/musical/etc. vein, Rosina is Dr. Bartolo’s ward in Barber of Seville (which I’m sure has been televised any number of times). Like Turpin and Johanna, Bartolo plans to marry her, although his motive is more money than lechery.
There are conservatorships.
If the woman is over, say 25, then e.g. research assistant / niece / secretary works great.
If she’s more like 16, then guardian is probably a safer choice, at least out in public.
Exactly where the cutoff in between belongs depends on local law and then-current custom.
Throckmorton P. Gildersleeve looks after his orphaned niece and nephew in the '40s radio show The Great Gildersleeve.
There’s Arnold and Willis on Different Strokes. They became the wards of their deceased mother’s boss.

There’s Arnold and Willis on Different Strokes. They became the wards of their deceased mother’s boss.
No, he formally adopted them. He is their legal father.

No, he formally adopted them.
Not until Season 2.
It also sounds like dying and leaving behind children of tender years was a lot more common IRL in e.g. 1880 than in e.g. 1980. As such writers of that era had lots more IRL examples of orphans. Culturally, they were a “thing”.
It happens that one of my younger relatives is a professional foster parent. Usually has 7 kids and manages them while living in a group home provided by the agency. That’s her full-time job. The duration of stay for any one kid within her home is all over the map, ranging from a couple weeks to a few years. I’d WAG the median at about 18 months.
Of the 20 or 30 kids I can recall the biographies of, exactly zero of them were fully orphaned by the death of both bio-parents. Far more common were single parents who got jailed or got afoul of CPS for drug use or domestic violence / child neglect. Even single parents being killed is real rare in foster circles here in 2024.
Based on what I can tell from a little bit of Googling, the legal setup is that when a kid is orphaned, they’re placed in the care of a guardian, and they’re defined as the “ward”. That terminology seems to be independent of whether or not the kid’s guardian is his next-of-kin or not; in fact the term “ward of the court” basically means a kid who doesn’t have any next-of-kin or defined guardians, and the court is in charge of them until they can have someone appointed as guardian.
So my suspicion is that the term "ward’ as used in goofy old TV shows was just a reflection of the common usage of the time for wards who weren’t within the family. I mean, if Dick Grayson had been Bruce Wayne’s nephew, he’d have been called that. But he was apparently just some kid that Wayne had got himself appointed guardian of.
Adoption makes it different- that’s the formal legal process of adopting a child as your legal child and heir. At that point, it would be appropriate for Wayne to have called Grayson his son, not his ward.

Nah, Jethro is “Cousin” Pearl’s son (I always thought Peal was the sister of Jed’s late wife) and is considered by one and all to be a “nephew” who lives with the Clampetts so he can go to a fancy city school and finish 6th Grade.
And of course, Pearl was still alive (she sounded a lot like Betty Rubble, and looked a lot like Kate from Petticoat Junction). Jethro was not an orphan. Despite always calling Jed “Uncle” (most likely because of the age difference), he was actually Jed’s first cousin once removed.

And of course, Pearl was still alive (she sounded a lot like Betty Rubble, and looked a lot like Kate from Petticoat Junction).
And, in fact, she was a recurring character at first, appearing in 22 of the 36 episodes in the first season. But, after that season, Bea Benaderet was cast as the lead in Petticoat Junction (created by Paul Henning, who had also created The Beverly Hillbillies; he and Benaderet had been longtime friends).
Due to this, Cousin Pearl was written out of the series, with the explanation of her having “moved back home” (though she had one more appearance, in a season 6 episode).
Going into the animated world, what were Jan and Jace to Space Ghost? They’re just listed as sidekicks (and I had no idea Tim Matheson was the voice of Jace).
Who was responsible for the Wonder Twins in the Justice League? They seemed like minors, and there seems to be nothing about them either.
The age of majority in English law was 21 until (fairly) recently, but the age to marry was 16 (now raised to 18).

(and I had no idea Tim Matheson was the voice of Jace).
Also the voice of Jonny Quest.
Speaking of which, what was the status of Hadji? Dr. Quest just seems to have picked him up in India one day.

Wards have essentially been replaced by the foster system.
This was the answer I had thought of after reading the OP.

Well, The Bradys and the Partridges added kids too.
I remember cousin Oliver on the Brady Bunch, but I don’t remember any kids being added to the Partridge family, and I was watching the show fairly recently on one of the retro TV channels. Was there a “lost” last season or something I don’t recall?

but I don’t remember any kids being added to the Partridge family,
They added a younger kid/singer, Ricky, to the cast in the final season, but I think he was a neighbor, and not adopted or “warded” into the family itself.

t I don’t remember any kids being added to the Partridge family
Yeah. They just traded in their drummer for a new model.