Keith Olbermann apologized to Houston news anchor Melanie Lawson Wednesday night on "Countdown," just one day after airing an embarrassing clip that showed Lawson falling out of her chair during a live broadcast.

The reason for Olbermann's apology? It turns out that Lawson has multiple sclerosis , which might help to explain the incident. According to a mutual friend of both the MSNBC host and the anchor, Lawson has used a cane for years.

But it appears that MSNBC wasn't the only cable news network to air the video. Fox News ' "Fox & Friends" also joked about the clip they called "Anchors Away" over the weekend, according to one angry viewer who wrote to media web site Houston Press :

I am very conservative politically and watch the Fox News cable channel from morning to night. Their political views align with mine and I do not trust the other media outlets which have a hard liberal bias.

However, the FNC show Fox and Friends Saturday which aired yesterday 3-27-10(6-9 AM)included a "funny" video segment of a Houston Anchor woman falling from her chair while on the air. The segment was called "Anchors Away" and was accompanied by raucus jokes and malcious commentary as the anchor fell to the floor on while on the air. That anchor was Melanie Lawson.

As much as I like and trust Fox politically, I wrote to them demanding that they issue a live, on air apology on the Oreilly program which will be aired on Monday 3-28-10 (7 PM).

Fox News may have broadcast the apology, but footage of it could not be found online.

WATCH: Olbermann's apology

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WATCH: Lawson takes a spill