Dannii Minogue admits it is a "great sadness" that she has a child and her sister Kylie doesn't.
The 45-year-old singer - who has six-year-old son Ethan with ex-boyfriend Kris Smith - has never been as maternal as her famous older sibling, and was always in awe of how the Wow hitmaker instinctively knew how to interact with their nephew Charles, now 10, and she didn't.
Though Dannii never had a strong desire to have kids of her own when she was younger, seeing Kylie - who is engaged to actor Joshua Sasse - deal with her heartbreak at not having a family has made her appreciate just how "blessed" she is.
She said: "Growing up, it was Kylie who always wanted kids and I never really did. When my brother Brendan had his little boy, I hadn't a clue even how to hold him. I remember being really impressed by Kylie because she just instinctively knew what to do.
"When he was a bit older, she'd be the one rolling on the floor with him, making him laugh his head off and I'd be thinking, 'What do I do?' When I got pregnant I was completely shocked.