In our Islam we know if you love Mohammad or religion the sign of love is to follow it not to celebrate in Birthday Mohammad didn’t celebrate for that. Islam didn’t do like this to celebrate in someone.we celebrate for E’ad Al Fater and E’ad Al Ad’dha.
I do certainly agree with you that we as Muslims have to adhere to very tradition of Holy Prophet.
However, the very term Tradition, to me, means something close to this: following very measures that Holy Prophet set as True Islam. In other words, there had been two distinctive dimensions to Holy Prophet's deed: Content and Form. Our actions must be conforming to the Content, but not necessarily to the Form.
For example, we have repeatedly heard that Holy Prophet donated bread and date to the poor. It's one of his deeds, which includes Content (i.e. being kind to the poor) and Form (i.e. donating some certain materials, including bread and date). We have to imitate the content (be kind to the poor), but not necessarily the Form (just donate bread and date). Now, let me ask, if somebody happens to donate Pizza, in your opinion, he is far away from Holy Prophet's tradition? I don’t think so: he "is kind to the poor", thus his act is conforming to Holy Prophet's standards, even though he does not follow the very 'Form' Holy prophet had been used to.
So there is a certain set of Objective Measures, or Contents, to which we have to subscribe. But there are too many forms which may assume those very contents. Some of these forms have been common and usual in the time of Holy Prophet, and consequently he practiced them. Some of them were not common in the time of Holy Prophet, and consequently he failed/refused to practice them; however it does not forbid us to practice them.
Therefore, I don’t think that we have to imitate every act that Holy Prophet did, and avoid every single thing he either failed or refused to do. And there is another reason to it: it's practically impossible.
Again, I do agree that the Forms we decide to practice should be conforming to the measures set by holy prophet. For example, the tradition of Holy Prophet was to show his happiness for Eids, i.e. Holidays. We may come to use some new Forms to show our happiness, but not the forms which may be in conflict with His Tradition (such as dance and drinking alcohol).
So, after all, Holy Prophet orders us to be kind to our mothers. Is there any problem if we dedicate a certain day every year to our Mothers? And is there any problem if we use birthday of a great woman, daughter of Holy Prophet, to do so? A stone and two birds: expressing our kindness to mothers (as the Holy Prophet ordered us) as well as his family (again as he ordered us).