Legendary astronaut Buzz Aldrin files lawsuit against two of his children, who are trying to take control of his finances

Legendary astronaut Buzz Aldrin, who has walked on the moon, is facing a major challenge at home — from his kids.

Andrew Aldrin and Janice Aldrin say their 88-year-old father is in declining health and want to be able to make financial decisions on his behalf. The NASA icon responded by filing a lawsuit, claiming they slandered him by saying he is suffering from dementia and Alzheimer's.

Business manager Christina Korp is also named in the lawsuit, filed earlier this month in Brevard County, Fla.

"Nobody is going to come close to thinking I should be under a guardianship," Buzz Aldrin told the Wall Street Journal in an interview last week.

Aldrin alleges in the lawsuit that the two children and Korp intentionally withheld "pertinent financial and business information" belonging to him. The suit claims that Andrew Aldrin and Korp transferred nearly $500,000 for their own use. They are accused of elder exploitation in the lawsuit.

Photos of Aldrin through the years:

The children are seeking control of their father's finances and want him to undergo a competency exam, according to the Wall Street Journal.

Andrew and Janice Aldrin said in a statement to the Journal that they are "deeply disappointed and saddened by the unjustified lawsuit that has been brought against us individually and against the Foundation that we have built together as a family to carry on Dad’s legacy for generations to come. We love and respect our father very much and remain hopeful that we can rise above this situation and recover the strong relationship that built this foundation in the first place."

Korp was fired by Aldrin last month, but continues to "represent herself" as an employee of the space legend, according to the lawsuit. She has knowledge of Buzz Aldrin's "cognitive decline," the children note in their request for an examination, according to the Wall Street Journal.

“What Andy is doing is saying to Buzz, ‘you’re old, you’re not in your right mind anymore because you don’t agree with me,'" Buzz Aldrin's lawyer Robert Bauer told the Journal.

A longtime friend of the astronaut said that Aldrin has never been great about financial matters.

"Buzz is a genius, he’s the smartest guy I ever met," Robert Tourtelot told the Wall Street Journal. "But Buzz has never been street smart."