His ex-wife Gail Jensen submitted legal documents before her own death in April (10), requesting to be named the administrator of his estate, claiming Carradine owed her money.
The actor's widow, Annie Carradine, hit back at Jensen's legal bid by filing her own claim for control of his estate in August (10).
And now Jensen's sister has taken up her sibling's fight, filing legal documents in Los Angeles County Superior Court to demand a portion of the star's estate, according to TMZ.com.
In the papers, she claims Carradine owed her sister $250,000 (£166,600) in royalties from cult TV show Kung Fu and the book Spirit of Shaolin, as well as $300,000 (£200,000) in tax payments she made on his behalf.
Annie Carradine previously claimed that the value of her late husband's personal property was only $40,000 (£26,600).
Kill Bill star Carradine was found hanging in the closet of his Bangkok, Thailand hotel room in June 2009. Investigators found the cause of death to be asphyxiation and Thai police reports suggested he died accidentally during a dangerous solo sex game.