In the second-season episode "The Chains of Command", Gilligan is discouraged because the Skipper has seemingly been kidnapped and no one will listen to him. Mary Anne gives him a stirring pep talk.
Hi-Fi Gilligan. A typhoon hits the island and the castaways plan to ride it out in a small cave, but there's not enough room for everyone. The men draw straws to see who will stay outside in the storm. Gilligan breaks his straw in half to save his friends, seeing as he's more expendable than them. When they realize what he did, the castaways leave the cave. If they can't all be safe, they'll be together. However, this ends up saving their lives when the storm destroys the cave immediately after they all leave.
"Love Me, Love My Skipper": When the other Castaways think that the Howells have snubbed the Skipper in party invitations, they boycott the Howell's party and plan one in the Skipper's honor instead.
At the beginning of the Beauty Contest episode, while everyone's arguing whether Ginger or the sophisticated Mrs. Howell is more beautiful, the Professor stands up and says he knows a girl who embodies beauty, sweetness, and warmth, whom he would choose as the most beautiful woman in the world — Mary Anne. The way Mary Anne blushes and smiles at the praise is unforgettable.
In "Slave Girl", the Professor and the Skipper both claim to be the titular girl's master so that her boyfriend will not challenge Gilligan to a fight for her.
From the same episode, when it appears that Gilligan will be challenged to a death match for the girl whose life he saved, the Professor, Mary Ann, and Ginger (the only three in the hut) agree that they will fight and die with him rather than simply letting him get killed.
"Where There's A Will" has a chain of these. The episode starts with the castaways all taking care of Mr. Howell when he falls ill. This prompts Mr. Howell to realize they're all like family to him, and he leaves them each a different industry in his will — not just random bequests, either, but chosen after he and his wife discuss which fit their personalities best. It ends with the rest of the cast mistakenly thinking Mr. Howell has died and conducting a funeral so heartfelt it moves him to tears before he reveals himself.
Real-life example. In 1992, several children suffering from cancer were granted a wish from the Make-a-Wish Foundation. Their wish? To finally rescue Gilligan from the island. Bob Denver himself donned the Gilligan costume and waited on a deserted island off the West Virginia coast to be rescued by the kids. After boarding the cruise ship carrying the children (the S.S. Minnow, of course,) he spent the rest of the day playing games with them. ::Sniffle::