Recently, Jill Duggar and Derick Dillard celebrated their son's birthday. Samuel Dillard turned 4.

Jim-Bob and Michelle were conspicuously absent from their grandson's birthday party.

They did, however, post a birthday tribute ... until they took it down.

It looks like they want nothing to do with Jill, Derick, or even their own grandsons.

The infamous Duggar Family Instagram account posted about Sam's birthday and the celebration.

The account shared multiple photos that Jill had shared.

It also praised Jill's brother James for his role in Sam's birthday surprise.

"James take the case as the 'funcle' (fun uncle)!!" the post began.

“Not sure who had more fun today," the caption read.

"But it was a blast being able to surprise Samuel for his 4th birthday by rolling up in a fire truck!" the post expressed.

The caption concluded: "Happy birthday, Sam! We love you!!”

Some fans were struck by what looked like dishonesty -- the implication that the whole Duggar family was there.

In reality, James arrived (in a fire truck) and Jana was also there, possibly with one of them chaperoning the other.

Some fans were disturbed that they would joke about a "fun uncle" under the circumstances.

An old, old expression for a sexual predator within a family is a "funny uncle."

Given the reality of who and what Jill's eldest brother, Josh Duggar, is, that seems way too close to home.

Fans weren't sure what to make of it. Was this posted with permission?

Was it, as some suspect, Jana posting for the family account, which many suspect that she has run for years?

Or did Jim Bob and Michelle just steal the photos from Jill and share them while pretending to be more involved in their lives?

We do not know.

What we do know, and what many followers quickly noticed, is that the post vanished from the Duggar Instagram page.

For a while, it remained on Facebook before winking out of existence on that older platform, too.

Immediately, fans and critics alike began to speculate on social media.

Was this something requested by Jill and Derick -- did they want their son's birthday removed from the account?

If so, was it because of how Jill's parents have treated them, or was it over something else?

Sam Dillard's special birthday celebration included a wonderful surprise from his 20-year-old uncle, James.

James arrived for the party with a firetruck.

Not a toy firetruck. An actual firetruck. What 4-year-old wouldn't be overwhelmed with excitement?

Their son turned 4 years old on July 8, and his proud mother shared the festivities the next day.

“Sam had a great 4th birthday yesterday," Jill announced on Instagram.

It was a day "beginning with papa @derickdillard getting donuts for breakfast and all his favorite snacks and some!”

“Then we had a blast hosting a last-minute water block party on the front lawn with some neighborhood friends," Jill shared.

They had a aprty "while the kids took turns testing the hoses and checking out the fire truck!”

James, she revealed, ahd arrived via firetruck. And Jana, photos made clear, was also there.

Fans have discussed how Jana and James may have only been there as aunt and uncle of the birthday boy.

Some wonder if Jana was there to chaperone James, and perhaps even vice versa.

After all, Jill is not part of the cult. Jim Bob would fear that Jill could influence any unmarried sibling one-on-one.