'Menace II Society' Star Samuel Monroe Jr.'s Mother Files For Conservatorship

The mother of Samuel Monroe Jr. -- the actor who has been hospitalized in Los Angeles on life support for months -- says he's been living with her for years ... and she's now asking a judge to put her in charge of his decisions ... instead of the woman who says she's his wife.

According to court docs, obtained by TMZ ... Joyce Patton filed a petition asking to establish a conservatorship for her son ... questioning whether he was ever legally married to his children's mother, Shawna Stewart.

Joyce also claims ... Sam has not lived with Shawna in more than 15 years -- and says for the past four years, he has been living with her.

His mom says Shawna has been collecting money from a GoFundMe set up for his bills ... as well as receiving his film residuals.

Shawna tells TMZ ... "Well, we will be fighting in court then. Everything will come out." She believes Sam didn't want his mother in charge of his finances or decisions.

The actor, best known for his work in "Menace II Society," has been hospitalized since April ... initially going in for a severe case of meningitis, which turned into MRSA pneumonia -- and from there, it seems one severe medical issue after another piled up.

Shawna previously told TMZ she was his power of attorney ... but was working along with the family on making decisions about Sam's quality of life.