All Blacks: Fatherhood converts Sonny Bill Williams from sulker to saint

Sonny Bill Williams admits he's learned life's toughest lessons when no-one else is around to see - like the early hours of the morning when fatherhood duties call.

The veteran midfielder will return to the All Blacks line-up on Sunday morning (NZ time), after a frustrating year that has largely seen him side-lined by injury.

Previously, that might have brought out the worst in Williams, as coach Steve Hansen recalls.

"Once upon a time, he would have sulked a lot about being injured and not getting games," says Hansen. "But he's matured into a really good human being.

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"He understands there is no point being down about it, so he is pretty positive. He is a positive person around the environment while he is injured, he just gets on with his trainings."

But Williams admits its hasn't been an easy transition and becoming a parent has helped.

"Love, to me, is shown at the most inconvenient times," he told Newshub's Ross Karl. "At 3am, when the kids are crying and my wife can't help me, because she's with the baby.

"You have to take those deep breaths and try to centre yourself. That has helped me in my professional life as well."

See more from Ross Karl's exclusive interview with Sonny Bill Wiiliams on Newshub, 6pm Friday

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