Frankie Muniz's fans are rallying around him after he posted a cryptic message about friendship on social media.

Here's the skinny ... in the late hours on Friday, the former child star posted to his X account, where he admitted he was having trouble sleeping amid friendship woes.

He wrote ... "Can't sleep. Hard when you realize your friends aren't really your friends."

It didn't take long for fans to catch wind of the melancholic upload ... prompting many to voice both concern and support for the "Malcolm in the Middle" alum. While some asked if Muniz was "good," others encouraged him to "hang in there."

Muniz has yet to elaborate on the specifics behind his apparent friend fallout ... as he didn't name names on X.

In fact, many were taken aback by his sad sentiment given his recent career news. We're, of course, talking about the upcoming "Malcolm in the Middle" revival set for Disney+ ... which will see Muniz reunite with his on-screen parents Bryan Cranston and Jane Kaczmarek.

No word yet on whether his on-screen siblings Justin Berfield, Erik Per Sullivan, and Christopher Masterson are set to appear on the new series.

Following the announcement, Muniz took to Instagram to voice his excitement surrounding the revival.

He added ... "Get ready, we can't wait for everyone to see what Malcolm and his family have been up to! #MalcolmInTheMiddle."

Here's hoping this drama has nothing to do with the upcoming series.