Prince William's heartbreaking wish for his kids

In new footage from this week's upcoming documentary about Princess Diana, Prince William opens up about how he keeps her memory alive for his young children.

And he said he's sure "Granny Diana" would have "loved them to bits".

"I'm constantly talking about Granny Diana," William said in Diana, Our Mother: Her Life and Legacy.

"Um, so we've got more photos up around the house now of her, and we talk about her a bit and stuff."

The documentary has been released to coincide with the 20th anniversary of Diana's untimely 1997 death.

"It's hard because obviously, Catherine didn't know her so she cannot really provide that level of detail," he added.

"So I do regularly, putting George and Charlotte to bed, talk about her and just try and remind them that there are two grandmothers. There were two grandmothers in their lives and so it's important that she know who she was.

Diana, Our Mother: Her Life and Legacy airs Sunday, 30 July, at 7pm only on Channel 7.

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