American tennis star Jessica Pegula, the world number four, provided an update on her mother's condition in a long Players' Tribune article on Tuesday.
The five-time grand slam singles quarter-finalist revealed her sister, Kelly, saved their 53-year-old's mother live by giving her CPR after their father woke up to her going into cardiac arrest nine months ago.
Kim, co-owner and president of both NFL franchise the Bills and NHL team the Buffalo Sabres, is back at home and doctors are "blown away" by her "miracle" recovery.
She is, however, suffering from significant expressive aphasia and significant memory issues and the family have come to the realisation that she is unlikely to resume her roles with the Bills and Sabres.
Jessica revealed that three months before her mother fell ill, her sister had decided to learn CPR.
She wrote: "Kelly called me one day and said she was going to get her CPR certification as a requirement for a job she wanted. I said: 'No way, I have been meaning to do that but haven't gotten around to it.”
"She relayed to me how nervous she was about it and hoped she passed the class. I remember her telling us what she was doing in our family group chat, and my mom even responded: 'Nice Kells! Now if we have a heart attack, you can revive us.'"
She added: "Today, my mom is still in recovery, and although it is the same answer every time someone asks me, it is true, she is improving every day. She is dealing with significant expressive aphasia and significant memory issues.
"She can read, write, and understand pretty well, but she has trouble finding the words to respond. It is hard to deal with and it takes a lot of patience to communicate with her, but I thank God every day that we can still communicate with her at all. The doctors continue to be blown away by her recovery, considering where she started, and her determination is the driving force of that."
Jessica was a quarter-finalist at the Australian Open last month, having been considering whether she should call time on her career.
She stated: "Suddenly, I went from 'Let's celebrate top 10 in the world' to 'Do I need to start thinking about my career after tennis a lot sooner than I thought?' 'Does my dad and family need help?' 'Maybe I should just go back to school and work for the family.'
"I am 28 and I take pride in being able to handle every situation thrown at me, but this was A LOT."
She was also hit hard by seeing Damar Hamlin collapse on the field while playing for the Bills last month.
"Then in January we came to some bizarre, messed-up, full circle moment." she wrote. "Buffalo Bills player Damar Hamlin suffered a cardiac arrest on the field during the Monday night game against the Cincinnati Bengals. My stomach sunk because it felt like the exact same thing all over again."
Last year's French Open women's doubles runner-up continued: "It has been a tough year, but at the same time I feel lucky and blessed. I am thankful she is still with us when other families may not have been so lucky.
"That she even had a chance at recovery when the first week in the hospital seemed so dim. Thankful for the doctors that aided in her recovery. Thankful that she is now home, that she gets to watch the Bills, Sabres and my tennis matches. She never watched my matches before, because she got too nervous. Now she watches all of them.
"Thank you to the Buffalo community for your patience. I know you have wanted answers and it took us a while to get there, but it finally felt like it was time. Thank you to everyone who has respected privacy and shown me and my family tremendous support throughout this ongoing journey."
