You could use either from or since in the present perfect.
In other tenses, from requires a start and end time point. In the present perfect, it is implied that the current time is the end point.
In fact, you can even drop the possessive pronoun most of the time because a listener will probably know the relative ages of the speaker and subject of the sentence from context.
I have known her from birth.
Which birth is being talked about changes if an older person is talking about a younger person or vice versa, (or if they're both salt the same same age, for that matter).
But it's automatically understood whose birth is being used for reference because of temporal logic (ie. if the speaker is older than the subject, then we know the subject's birth is being referenced).