"at the" is not correct. "At my brother's wedding" is correct. "to my brother's wedding" is also correct. It depends on the context of the statement. "At my brother's wedding, I met a really fabulous guy." "When I went to my brother's wedding, I met a really fabulous guy." "Are you going to my brother's wedding?" "Will I see you at my brother's wedding?" Each pair of these sentences mean the same thing and are grammatically correct.

It depends on what you are trying to say... You use AT when referring to a time or place: -There was a lot of food AT my brother's wedding. -I am AT my friend's house. -Where are you AT? You use TO when referring from a move from point A to point B. -I am going TO my brother's wedding. -Please move it from here TO there. -She traveled TO France. There are also special exceptions for these two prepositions, but we can save that explanation for another day :)

Without any further contextual information, "At my brother's wedding" means you are physically there already. "To my brother's wedding" can mean that you are not there yet but is intending to be there.

This depends on the context. On Saturday I will be at my brother's wedding. - The word THE is not required. (AT - location) I will be going to my brother's wedding on Satuday. (TO - pass something, move towards something, movement from one place to another). Additional note. When forming a question using the verb 'to be', reverse the word order as follows: It is correct to say. Statement, normal word order Is it correct to say? Question, reversed word order.

It is a matter of context: I am going to my brother's wedding , I will be at my brother's wedding