Gordon's lawyer did not return ABC News' request for comment about the lawsuit. Gordon did tweet a message of hope for Brown Wednesday, which is now protected and blocked from the public.
Gordon’s mother also told McGraw about the argument, but that "Nick walked away from the argument [and] went to another bedroom to fall asleep.” She did not say anything about alleged assault.
The lawsuit also claims Brown and Gordon got into a "loud argument" just before she was found unresponsive in her Georgia home at the end of January. Brown was found "with her mouth swollen and another tooth knocked out," the document claims.
After Brown was hospitalized, the suit alleges, Gordon stole more than $11,000 from Brown.
Brown was found face down in her tub Jan. 31 by Gordon and a friend, and has been in treatment, hospitals and rehab ever since. Her family said Wednesday she is in hospice with irreversible brain damage.
"Despite the great medical care at numerous facilities, Bobbi Kristina Brown's condition has continued to deteriorate," her aunt Pat Houston told ABC News in a statement Wednesday. "As of today, she has been moved into hospice care. We thank everyone for their support and prayers. She is in God's hands now."
Separately, the Fulton County District Attorney Paul L. Howard, Jr. told ABC News today that "The Roswell Police Department has forwarded its investigative file to our Office. In view of the new circumstances regarding the health status of Bobbi Kristina Brown, we will be reviewing the case with greater interest. An announcement regarding a charging decision, if any, will be made at the appropriate time.”
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