Michael Middleton feared that without help she would struggle just like Diana. But in a solemn chat, the heir vowed that Kate would have his undying support.
"William told him he would do everything to ensure history didn't repeat itself. He pledged to look after and protect Kate," the Mirror quoted a source as saying.
"He saw first-hand, albeit as a small boy, how hard Diana found it in the public eye. She could not cope. Michael had made clear his concerns but he was reassured," the source said.
The 20-minute heart-to-heart at his future in-laws' home in Bucklebury, Berks, came after William had popped the question to Kate in Kenya. And he repeated his vow after their engagement was made public this week.
"I want to make sure they have the best guidance and the chance to see what life has been like or is like in the family. That's almost why I have been waiting this long, Williams said insisting he was "massively" protective of his fiance and her parents.
"I wanted to give her a chance to see in and back out if she needed to before it all got too much.
"I'm trying to learn from lessons in the past. I wanted to give her the best chance to settle in and see what happens on the other side," he said.
Kate admitted life as a royal wife was "a daunting prospect" but voiced her confidence that her husband-to-be would guide her through it.
"Hopefully I'll take it in my stride. And William is a great teacher, so hopefully he'll be able to help me along the way," she said. (ANI)