"Cada um tem seus ideais."

[jojoke]

each one = 3rd person singular - each one has his ideals

[soulzy]

If this translates to "Each one has ITS ideals", how would you translate "each one has their ideals"? I would have thought it was the same in portuguese.

[erudis]

It's the same. I actually thought that was the suggested translation, because things usually don't have ideals. In any case, your translation works just as well.

[Lingodingle]

In English it would have to be, "Each one has his/her ideals since the subject is "each one".