John's birth was met with rejoicing Luke 1:58
Issac/Abraham Genesis 21:8. It was custom for children to be weened on their 3rd birthday, and Abraham provided a great feast on that day. Please research this for yourself as far as weening goes.
There are more, but the real question is what is the WT reasoning on not celebrating birthdays? Wasn't it because Herod had John the Baptist beheaded and Pharaoh had the baker killed. So someone died and that is the reason no? Well then afternoon naps should be held in the same regard. No good JW woman should be giving their child a nap in the afternoon!!!!! 2 Samuel 4:5-7