It’s a well-known fact that in Spanish (although not exclusively) the meaning of certain words is differentiated through the use of a tilde (which in this case is a diacritical sign, or signo diacrítico in Spanish). E.g. se is a pronoun and sé is a verb (the first person singular of saber, i.e. to know). The same goes for mi (pronoun) and mí (possessive determiner).

Well, what happens with mi and mí also happens with ti and tí. I.e. es para mí, es para tí.

Another, better, example would be mi casa, mi coche and mi amigo changing to ti casa, ti coche and ti amigo.

As you can see, the tilde is used, at times, in combination with ti to differentiate the meaning of the word.