It does happen everywhere, and it shouldn't be a problem as long the ''leaders'' of the clans speaks for everyone and thinking about the team and not about his mate from the same country. I remember we had the problem at Ajax with Zlatan, Mido, Van der Meijde against Sneijder, Van der Vaart and Heitinga. It's escalated so much Zlatan injuried Van der Vaart on purpose in an friendly match between Sweden-Holland. As long you have a true captain like Zanetti different groups doesn't matter as long as you do your job on the pitch and training ground.
Icardi showing himself a true captain lately and I like that, it shows he is growing as a player and as a person. How good must it feels for Lautario to come to europe play for a big club like Inter and having the teams captain and topscorer welcoming you like your family. For young players it is most important they feel like ''home'' especially when you come to Europe and a big city like Milano. I really hope and think this partnership of Icardi and Martinez could be like the Yorke-Cole partnership or Henry-Bergkamp, special players who have a connection with eachother.