The episode "The Perfect Gift" has Johnny trying to raise money to buy his mom a pair of bunny slippers. He fails but Susie tells him to tell his mom he loves her. He then admits just that and what a great mom she is with his mom right behind him as he does so.
"Date with an Antelope": Even if she is well, an antelope, Johnny was still gentlemanly enough to treat Carol with kindness by taking her out on a date.
Same thing with the episode where he dates a werewolf, even consoling her when she cries over scaring people with her frightening appearance. Of course, even Johnny has his limits when it turns out her secondary curse means she turns into a George Constanza-esque man who collects stamps on Wednesdays.
The episode where Johnny is lost in an Australian wildlife park, he's adopted by female kangaroo, and initially isn't accepted by the rest of the flock, until a kangaroo hunter named Boomerang Jack tries to catch his adoptive mother. Johnny beats the crap out of him, because "nobody, and I mean nobody hurts Johnny's mama!"