Peter Hillary said the public mourning for his father last year was impressive. Sir Edmund Hillary -- who gained international fame in 1953 when he and Tenzing Norgay reached the summit of Mount Everest -- died Jan. 11, 2008, at 88.

His death was announced by New Zealand Prime Minister Helen Clark and he had a state funeral at Holy Trinity Cathedral in Auckland and a memorial service at Windsor Castle attended by Queen Elizabeth II.

"They were extraordinary events, but on the other hand they weren't ideal for family grieving and coming to terms with it all," Peter Hillary said.

Peter Hillary said the family will gather Sunday at Anawhata, New Zealand.

"It's a time to think about dad and what he did, and what he meant to us all," the younger Hillary said.

Sherpas reportedly plan to mark the anniversary of the gamed mountaineer's death with a ceremony near the mountain.