When it comes to famous families in the AFL, certainly at Hawthorn, there's few greater than the Kennedy clan.

John Kennedy Sr played 164 games for the Hawks and coached the club for 298 games, delivering the 1961, 1971 and 1976 premierships.

John Kennedy Jr played 241 games, helping claim the 1983, 1986 and 1988-89 flags.

His son, Josh, had played 13 games for the Hawks - including the final nine of last season - before he and former Hawks teammate Ben McGlynn were traded to the Swans last October.

The Kennedys were disappointed at the time and that feeling remains as Josh, enjoying a strong season at his new club, prepares to take on the Hawks this week in a Sunday matinee at the MCG.

"He was disappointed to leave," his father, John Jr, said, stressing he didn't want to open up old wounds.

"It's going to be difficult enough for him without me having to weigh in.

"He is just settling in there now and I really don't want to make an issue of it."

It won't be the first time, however, a Kennedy draped in brown and gold tradition has taken on the "family club".

Kennedy Snr, remember, emerged from an eight-year coaching hiatus to lead North Melbourne between 1985-89.

He would fail to win a match against the Hawks, although he started brightly with a shock draw at the MCG against a club enjoying its finest era.

So, how will it feel watching his grandson this week?

"It's nothing new, we have had plenty of this," Kennedy Snr said, politely declining to discuss Josh.

It's clear Josh's departure last year remains somewhat of a sore point.

He was offered only a one-year contract by the Hawks, compared to three years by the Swans.

However, backpagelead.com.au understands that if there had been encouragement to stay, then Kennedy, 21, may well have rolled the dice and extended the family tradition with the now Waverley-based club.

Instead, it's believed Kennedy was bluntly told he would be about the sixth or seventh preferred midfielder on coach Alastair Clarkson's list, meaning he faced long stints in the VFL without any real hope of senior selection.

When Swans mentor Paul Roos flew to Melbourne, emotionally embraced him and said there was a major role awaiting him in the Harbour City, reality - rather than sentiment - hit home.

In return for Kennedy and McGlynn, the Hawks received draft picks 39 (Sam Grimley), 46 (Ben Stratton) and 70 (Matt Suckling) from Sydney - a deal that continues to irk some former Hawthorn champions.

Kennedy has played in all nine games this year, has had at least 16 possessions in each and attracted praise from Roos for his hard-work at stoppages - an area of pride for the Swans.

He faces an enormous test this week against the likes of Sam Mitchell, Luke Hodge, Brad Sewell and the suddenly rejuvenated Hawks, giving aggrieved fans a first-hand opportunity to judge further if the trade was the right call.

"So far (he has been good) but they (Swans) have got a lot of injuries. When you take the best four or five players out of anyone's side, they are going to struggle a bit," John Jr said.

"They are going to have their work cut out."

When John Jr, then a key midfielder in the Hawks' dynasty through the 1980s, took on John Sr and North Melbourne, he played some of his best football.

Whether it was a result of a son trying to impress his father, or the fact the Kangaroos weren't the strongest team at that time, is debatable.

Kennedy wouldn't say.

"When dad was coaching North, I tried to play just as I did against other teams but I did play okay, much to his annoyance," John Jr said with a laugh.

Expect Josh to at least also play "okay" this week. If emotion does take hold, he could do worse than act on his grandfather's immortal words at half-time while coaching Hawthorn in the 1975 grand final against North Melbourne: "Do! Don't think, don't hope. Do!"