Welcome to the forum Red tomato.
The non birthday celebration is just another twisted up doctrine that was made up by the many corrupt ignorant leaders of this religious organization.
True it may have had pagan celebratory origins but that's not how or why individual birthdays are celebrated today.
Its done so out love and respect for an individual not in spiritual ritual sense as it was was.
Jesus's greatest commandant was to love one another, so have as many birthdays as you want and keep on loving as many people as you want or think you should.
Make someones day special and they may in return make one day special for you too.