The presenter, 49, opened up about life with her father Andrew to coincide with the launch of the Memory Walk with the Alzheimer's Society, explaining that she's 'grieved' for the parent she once knew.
'I have grieved the loss of my old dad,' she said. 'But we are forging a new relationship, a different one - one where perhaps he might need me more. Our dynamic has changed, but he's still my dad.'
'My dad is very charming, everyone he meets falls in love with him. That's one thing that hasn't changed. He still gives the best hugs and my kids adore him. Since he's had Alzheimer's, he has become calmer and kids respond very well to that.'
'The person I do worry about is my mum. It's a lot, watching the man you love struggle and I know it's tiring for her. Each day is a blessing. We as a family are learning to adapt fast. Each step we discuss together.'
Back in April, Davina revealed her fears that she could get Alzheimer's herself, admitting she had recently called her doctor in tears over her worries.
The mum of three spoke to Good Housekeeping magazine about the concerns, and even admitted she's called her doctor several times in 'floods of tears' over fears that she could follow the same fate as her father and grandmother, who has been suffering with dementia for the past two years.
Davina said: 'I have called my doctor twice in floods of tears saying "I've definitely got Alzheimer's disease".
'She is so nice to me and says, 'If you had Alzheimer's, you wouldn't be calling me about it.'
Thankfully the TV star's doctor has assured her she has nothing to worry about, reminding her of the busy lifestyle she leads and 'good health'.
'She has told me I'm only forgetful because my inbox is full and I have cognitive overload. I don't drink, I don't smoke and I am in good health. If I get ill, I get ill - it's a lottery. None of us knows what's going to happen around the corner. You just have to enjoy life.'
Speaking about how her family members are coping with the illness, she explained that both her dad and gran are sadly getting worse but calls them both 'inspirational'.
'In certain aspects he [Davina's father] is getting worse - his short-term memory is really a struggle.
'My lovely granny is very confused now, but she is happy. They are both pretty inspirational.'