tWitch's mother is committed to defending her son's legacy ... declaring recent claims about her late son are totally bogus -- becoming the latest family member to call out his widow, Allison Holker.

Connie Boss Alexander posted a statement to Instagram Thursday morning ... writing the family is completely appalled by the "misleading and hurtful claims" floating around about her son.

Alexander explains she can't let these accusations go unanswered ... adding she refuses to sit idly by while her son's legacy is tarnished.

The last couple years -- since Stephen "tWitch" Boss died by suicide in December 2022 -- have been all about healing and working to connect with tWitch's kids, Connie adds ... but, now she says "Our family will ensure his name and memory are protected, and we are committed to defending his honor."

Worth noting ... Connie never mentions Allison by name -- but, it's pretty clear she's referring to her son's widow if you read between the lines.

ICYMI ... tWitch's family came out earlier this week and started slamming Holker on social media -- after she claimed she found drugs in a shoebox just before tWitch's funeral and said she's including some of tWitich's personal journal entries into a memoir she's written.

Family members started lobbing accusations at Holker ... claiming she made them sign an NDA to attend tWitch's funeral and that she was actually the one using drugs.

Holker went on social media to respond to all of the accusations ... explaining she only shared the info because she hopes to help anyone else with a family member who might be struggling like tWitch.

Clearly, that response didn't placate tWitch's family ... stay tuned.

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