What shall my 2,5 year old son do in the situation when his peer plays naughty games with him?

My son meets regularly a toddler girl (3yo), his friend, our neighbor and a follow-mate in kindergarten (let us call her a friend from now on). Either when met in the kindergarten or at home during their play they get to a point when my son is teased by his friend so much that he be hits or bites her. She starts crying and my son gets recognized an aggressor and culprit.

First we strongly requested him not to hit or bite his friend and any human in general. Now I fell that I should advise him how to cope with his frustration rather than telling him what not to do.

Let me give a couple of examples not to be too general. AT HOME: They are playing at home, he has a toy, his friend wants and takes it. Never mind, he takes another toy, however, she takes it again. AT A PLAYGROUND: She is climbing a ladder (towards a toboggan), he wants to slide a well. Well, he is waiting her to climb up and slide, however, instead of climbing she is lingering and makes a step back.

I see that such situations are frustrating for my boy. What response shall I teach him? On one hand I do not want him to be aggressive, on the other hand I want to find a fair solution for him so that he does not only play a role of a fool who gives up and gets out of her way.

Obvious solution not to put them together is not that easy as they are frequenting the same kindergarten.

What shall my 2.5-year-old son do in the situation when his peer plays naughty games with him?

My son meets regularly with a toddler girl (3yo); his friend, our neighbor and a follow-mate in kindergarten (let us call her a friend from now on). Either, when meeting in kindergarten or at home, during their play they get to a point where my son is teased by his friend so much that he hits or bites her. She starts crying and my son gets recognized an aggressor and culprit.

First, we strongly requested him not to hit or bite his friend and any human in general. Now I fell that I should advise him how to cope with his frustration rather than telling him what not to do.

Let me give a couple of examples not to be too general. AT HOME: They are playing at home, he has a toy, his friend wants it and takes it. Never mind, he takes another toy. However, she takes it again. AT A PLAYGROUND: She is climbing a ladder (towards a toboggan), he wants to slide a well. Well, he is waiting her to climb up and slide. However, instead of climbing she is lingering and makes a step back.

I see that such situations are frustrating for my boy. What response shall I teach him? On one hand I do not want him to be aggressive, on the other hand I want to find a fair solution for him so that he does not only play a role of a fool who gives up and gets out of her way.

Obvious solution not to put them together is not that easy as they are frequenting the same kindergarten.