False Minecraft Skins

When in multiplayer, the other player sees me as the default skin when on my end, its my homemade skin. Then the game will switch our skins. So my freind will have my skin when in my perspective, she has her skin, in my perspective, I have her skin, but in her veiw, I have the defalt skin. To make matters worse, I deleted the default skin and it still appears in game. I dont know what to do. If this helps, my gamertag is Ethan Power2016, and my friend(sister) is SarahEBrown.
If this is a duplicate, I do Apologize for ruining your important work!