The Karate Kid and The Karate Kid
The Karate Kid appears in the credits of The Karate Kid.
Proty was a member of the Legion of Super-Pets with Krypto, who belonged to Superman, who defeated Mandrakk with Nix Uotan.
Three is pretty good, I forgot about Final Crisis in trying for a hard one. Although, most versions of Kal-El would not use an ownership verb to sum up their relationship with Krypto, IMHO.
Karate Kid was in the Legion with Superman, who was in the Justice League of America with Zatanna, who mentored Tim Hunter, who was also mentored by Mister E.
John Fox is a descendant of Wally West, who was mentored by Barry Allen, who was in the Justice League with Billy Batson, who was in the Squadron of Justice with Bulletman and Bulletgirl, who were the owners of Bulletdog.
Indigo-1 indoctrinated Sinestro into her corps, who had previously indoctrinated Kyle Rayner into his corps, who was in the Titans with Raven.
How about Golden Glider and Green Arrow
Golden Glider is an enemy of The Flash, who was in the Justice League with Green Arrow.
Loma Shade and Adam Evans
Loma Shade inherited the M Vest from Rac Shade, who was in Justice League Dark with Zatanna, whose cousin is Zachary Zatara, who was in the Teen Titans with Kid Devil, who was later in the Teen Titans with Static, who protects Dakota City with Rubberband Man.
You’re seriously amazing, HCQ!
Dex-Starr and Lou
Dex-Starr was in Justice League Odyssey with Azrael, who has on multiple occasions fought The Joker, who previously owned Lou.
Mister Bones was in Infinity Inc with Al Rothstein, who was in the JSA with Captain Marvel, whose close ally is Tawky Tawny.