But, a year later, it appears that Prince Charles has taken over that role and, by all accounts, is performing admirably as a single parent.
In fact, some Britons are now critical of Earl Spencer's funeral-oration pledge to "do all we can to continue the imaginative and loving way you were steering these exceptional two young men so that their souls are not simply immersed by duty and tradition, but can sing openly as you planned."
As one critic put it, aunts and uncles shouldn't be telling a father - especially if he is the Prince of Wales - how he should bring up his sons.
Among the warmer moments Charles and his sons shared with the press were a skiing trip with both to Canada earlier this year and a visit with Prince Harry to Paris to watch a soccer game and meet the Spice Girls.
The British public has taken notice.
"He's done quite a good job, dedicated and sincere, and I think most people have been quite impressed with what he's done," one royal-watcher said.
Charles has managed to keep his boys out of the public eye, maintaining a strategy that says they are children first, and public personalities very much second. They may later take their place on the world stage as members of the royal family, he has said, but for the moment, they need to be looked after as children and treated with sensitivity.
The British press appears to have adopted a self-imposed code of conduct this year to protect the boys' privacy.
The motherly influence on the boys these days is that of their nanny, Tiggy Legge-Bourke.
Royal watchers say William in particular has shown a new maturity in the year since his mother's death. His younger brother, Harry, had great difficulties in the early days of his mourning and is now coming around, they say.
Many in Britain expect both boys to mature considerably once the traumatic events of his one-year anniversary have passed.