Katherine Jackson -- Could Lose Millions in Perks

The plot to turn Katherine Jackson against the Michael Jackson Estate has backfired in the most ironic of ways ... because the money grab could end up costing Katherine millions in perks.

When Katherine was appointed guardian of Paris, Prince and Blanket, the Executors gave an allowance of $60,000 per month for the care of the children ... that's $720,000 a year. Less than a year later the judge increased the 60k to 70k, and that would make the yearly take $840,000.

The judge is now in position to strip Katherine of guardianship altogether. If that happens, the executors will almost certainly petition the court to funnel the money in TJ's direction, since he would be caring for the children.

Katherine never had control of the money for the kids, but she enjoys a lot of the perks the kids get, and that goes away if she loses guardianship. She would still, of course, retain the allowance she personally receives from the Estate.

Short story ... Randy, Jermaine, Janet and Rebbie set out to turn Katherine against the estate so she could get more money during her lifetime -- money she could dole out to them -- but the plot may have actually screwed Katherine.