We propose to our many readers with numerous children the following:
(A) if the child was born on a Sunday, celebrate his birthday once every three years;
(B) if the child was born on an ordinary weekday, considering that he was not privileged to be born on the Lord's Day, you may compensate this by celebrating it every other year.
That way, you will be able to dedicate more time to each child's birthday and learn more about that child. Natural yearly cycles are just so overrated!