Oh, Rudy.

The news that Keshia Knight Pulliam — who played Rudy, the youngest daughter of Cliff and Clair Huxtable,  for 177 episodes of  The Cosby Showhad accompanied Bill Cosby to court on Monday for the first day of his sexual-assault trial made me sad.

Because whatever the man on whose show she spent much of her childhood may or may not have done, I'd hoped, naively, that we might be able to leave Cliff Huxtable out of it.

As I wrote back in 2014, when TV Land pulled its Cosby Show reruns in the wake of  the controversy reignited by comedian Hannibal Buress calling Cosby a rapist  (and when I still couldn't imagine the nearly decade-long accusations against Cosby would ever come to a jury), I don't know that we need to lose The Cosby Show over this.

And we haven't: Cable channels TV One and Bounce TV still carry the show.

Don't get me wrong. I believed Andrea Constand back in  2005. I believe her now. That belief carries no force of law, and I'm not on the jury, but it does mean that I get how hard it can be to think of Cosby as America's Dad.

Cliff, though, is another matter.

Pulliam may well be supporting a friend in trouble, and I respect her for it. But her presence, almost certainly part of a well-planned public relations campaign on the part of the defense, also encourages us to conflate Cosby and Cliff, and what's good for one isn't so good for the other.

We're used to separating actors from the roles they play. We have to be.

Here's what I wrote about that in 2014:

I grew up watching The Wonderful World of Color (in black and white, since we didn't have a color set) when Walt Disney still hosted it. He was not, I now understand, quite the nice man he seemed. My warm feelings for the show remain intact.

TV Land's still running Hogan's Heroes, whose star, Bob Crane, later murdered, seems to have been something of a pioneer in the videotaping of his sexual encounters. Whether all the women involved knew they were being taped isn't entirely clear.

I'd like to think that Col. Hogan wouldn't have done something like that, but, then, they didn't have video cameras in World War II prison camps, did they?

Because, again, it's all pretend.

The Cosby Show, which ran from 1984 to 1992 on NBC, was a special kind of pretend. Not just because it featured an African-American, upper-middle-class family, but because two professionals, a doctor (Cosby) and a lawyer (Phylicia Rashad), were raising five children without losing their minds.

Cliff's job as an obstetrician always struck me as a bit of a fantasy – how many ob-gyns, even those with a home office, are around the house that much during the day? But Clair? Clair may have made motherhood look easier than I already knew it to be, but I appreciated that she made it seem doable, even for someone with a demanding job elsewhere.

The Cosby kids were more interesting than a lot of sitcom kids, but it was very clear that they were not running the show that was their lives.

Clair and Cliff were.

Behind the scenes, the strings were pulled by the man whose co-stars and associates referred to him as "Mr. Cosby," the man whose private life seems finally to have come back to bite him.

But however badly Cosby may have treated some of the women in his real life, The Cosby Show was a portrait of an enviable marriage, one built on love and mutual respect.

And proof that whatever he's done, Bill Cosby on some level really did know better.