Female? No
Active? No
Danish? No
Ever had a team mate from Kazakhstan? No
Born in the southern hemisphere? No
Ever raced in China? No
Active after 1/1 2010? No
European? Yes
Active after 1/1 2000? No
From landlocked country? No
Any relatives who are/were also pros? Yes*
Parent(s) also pros? No
From country with GT? No
Female relatives who are/were also pros? No*
Ever ridden a GT? No
Active before Davide Rebellin turned 20? Yes
Brother(s) also pros? No*
Son(s) also pros? Yes*
Active before WWI? No
Active after WWII? No
Walter Eibegger? No
Grandson(s) also pros? No*
Podium in a monument? No
Podium in Paris - Tours? No
Ever ridden these races? No
What's with the "*"? The use of the word 'also'
Wife also pro? No*
Was he a pro? No
Did he ride as an amateur? Yes
Son(s) pros? Yes (singular)(he has two sons who cycle/d, one of whom was pro)
From a duchy? Definitely not
More famous than his son? Definitely not
Ever competed at the World Championships? No
Alive after WWII? Yes
Paticipated in the Olympics? No
Relatives who has competed at the WC? Yes
Belgian? No
Other relatives who also cycled competitively? Not to my knowledge (but the son is the most important one)
Is his son definitely his son? Short of a DNA test to the contrary being evidenced, yes (they certainly exhibit certain shared characteristics as cyclists for a start)
(Pro) son still active? No
The son won multiple GTs? No
And even the Worlds maybe? No
And a monument or more? No
But you will definitely know the son unless you've been living under a rock.
So the bit about his exact relation to his relatives who also cycled being in question isn't actually true? I found the way that question was phrased confusing, and clearly I have misinterpreted what you meant by it. In which case:
Are his exact relations to those relatives in question? No