"A beautiful Mother’s Day morning spent with my beautiful husband, mum, children and little boo boos." Lisa began the post.
"It was difficult to hide my sadness today... there are so many emotions... always being tugged from happiness to sadness. 😞"
The swimmer went on to emphasise the importance of the never-ending "mother's role", stressing it is to "protect", "comfort" and to "teach what's important... to be kind to others, to follow your dreams... and then when you leave our nest, to do your best."
The 58-year-old continued: "To all our children, on earth and in heaven, you are our greatest achievements and our greatest loves.
"I am your mum and I love you with everything I have.
The sweet message was soon inundated with comments of support.
"Happy Mother’s Day Lisa. You are an amazing human being. An extremely hard day for you 🙌❤️" one touched user wrote.
"Jaimi’s garden is looking so beautiful 🌸" another penned.
Some really resonated with Lisa's grief, having experienced loss themselves.
"Lisa, after losing my beautiful 17 year old son last October, every single word you write resonates deep in my soul. Thank you for sharing your journey of grief, and just know you’re not alone ❤️" a user bravely shared.
Lisa and Grant announced Jaimi's tragic passing back on September 14th last year.
“It is with a very heavy heart that Lisa and I confirm that our beautiful daughter Jaimi has lost her battle with a long-term illness and passed away peacefully in hospital this morning in the company of loving family," Grant said in an official statement on behalf of the family.
“Jaimi will forever be remembered as a caring, bright and loving soul who always put others before herself.
“Our hearts are broken and the pain is immense but we must move forward cherishing every wonderful moment we got to share with our treasured first child.
“It goes without saying that this is a very difficult time for family and friends and we trust we will all be allowed to grieve in privacy” he said.