Homeward Bound: The Incredible Journey
Frank was first mentioned by Kate to the Seavers and he will be the one who looks after Chance, Shadow and Sassy, while she will be gone for a horse riding for a few days.
After Chance, Shadow and Sassy left the farm to return back home worrying about the Seavers, Frank arrives at Kate's ranch and begins to call Chance, Shadow and Sassy, but they are nowhere to found. Frank then enters the farm to find the note that Kate left for him, but he thinks that she takes Shadow, Chance and Sassy with her and feeds her animals.
A few days passed, Frank was last seen greeting Kate who just returned from her horse riding. He asks Kate how's the horse riding and she replies that it's fine and asks if he take Chance, Shadow and Sassy and she replies that she did not take them for a horse ride. Frank then tells him that the note she left that she take them with her. Frank and Kate then realize that Shadow, Chance and Sassy had already left the farm and contact the forest rangers. The forest rangers informed that they did not see Chance, Shadow and Sassy and only mountain lions, bears and other animals, Kate then asks the forest rangers if anyone else in the park she can called and they give her and Frank tells her they done everything they can and will find them. They then contact the Seavers informing them that Shadow, Chance and Sassy are no longer with them anymore. Frank was not seen afterwards it can assumed that Chance, Shadow and Sassy are reunited with the Seavers.