A question about the following sentence

[poli]

Vamos a organizarle una fiesta a mi abuela el próxomo otoño.

As a non-native speaker, it sounds wrong to me.

I would write: Vamos a organizar una fiesta para mi abuela (en) el próximo otoño.

Is the way I write it wrong?

[JPablo]

Vamos a organizarle una fiesta a mi abuela el próximo otoño.

As a non-native speaker, it sounds wrong to me.

I would write: Vamos a organizar una fiesta para mi abuela (en) el próximo otoño.

Is the way I write it wrong?
The way you write is not wrong. But probably "para el próximo otoño" will be better.

That is, "en el próximo otoño" could give the idea that you are going to do the organizing action during the fall season... Not that the party for your grandma will happen in autumn...

The "original" "Vamos a organizarle una fiesta a mi abuela el próximo otoño." sounds "normal" to me, although it could be ambiguous too, as I say above...

I'd personally would use "para el próximo otoño" if the party is happening then...

[AngelicaDeAlquezar]

In daily speech, it's a very commonly heard way to say that the party for grandma will be held some time in autumn.

@Poli: Your sentence is not wrong, but the original one isn't either. If what causes you trouble is "organizarle a mi abuela", this sort of redundancy is quite common, at least in Mexico, and it's not felt wrong.

[poli]

Thanks both of you. It's true that the indirect object pronoun in the sentence is nothing I would ever have used in this case, and I questioned it. It is good to know that it's an acceptable option.

[wrholt]

Ah, yes, sentences similar to the one that Poli cites sometimes surprise me and remind me yet again of how the "indirect object" (scare quotes intentional) in Spanish has a much broader range of applications and potential meanings than the indirect object (lack of quotes intentional) in English. And like Poli I am much more likely to produce something like his alternative than something like the original.

[Perikles]

Ah, yes, sentences similar to the one that Poli cites sometimes surprise me and remind me yet again of how the "indirect object" (scare quotes intentional) in Spanish has a much broader range of applications and potential meanings than the indirect object (lack of quotes intentional) in English. Yes, I think this is a real problem for English speakers used to a quite specific indirect object. The Spanish one would include, say, se le murió, which in English would normally be called an ethic dative, or le ensuciaron el coche, where English wouldn't use an indirect object.