62 years ago - Alfred Pennyworth is born to the valet & cook of the Wayne family. He grows up alongside Thomas Wayne, making regular trips back to England.
44 years ago - 18-year-old Alfred Pennyworth leaves for England to join the army.
42 years ago - 20-year-old Alfred Pennyworth completes his specialized training and is selected as the field medic for an elite British special forces team.
36 years ago - 26-year-old Alfred Pennyworth finishes his tour of duty & becomes an actor on the London stage.
33 years ago - 29-year-old Alfred Pennyworth receives word that his father is dying. He returns to Wayne manor and meets young Bruce Wayne. He helps him outsmart a bully, and decides to stay for him.
31 years ago - 31-year-old Alfred Pennyworth becomes Bruce's legal guardian after Thomas and Martha Wayne are killed. He recognizes Bruce's psychosis and tries to channel it into something healthy.
25 years ago - 37-year-old Alfred Pennyworth is Bruce Wayne's only connection to the outside world while he travels the world. Alfred will sometimes travel to meet him, maintaining the illusion that he is in boarding school.
15 years ago - 47-year-old Alfred Pennyworth becomes Bruce Wayne's valet & medic as he becomes Batman.
14 years ago - 48-year-old Alfred Pennyworth becomes a surrogate father to Dick Grayson when Bruce Wayne takes him in.
5 years ago - 57-year-old Alfred Pennyworth is instrumental in convincing Bruce Wayne to take on Tim Drake as Robin.
4 years ago - 58-year-old Alfred Pennyworth travels to Europe with Bruce Wayne as he seeks out treatments for his broken back. Unable to watch him torture himself, Alfred tenders his resignation.
3 years ago - 59-year-old Alfred Pennyworth is sought out by Dick Grayson, and convinced to return to Bruce Wayne. He is stalked by Victor Zsasz during No Man's Land, but manages to fend him off until he is saved by Cassandra Cain.
Alfred poses a particular challenge, because he's given SO much narrative weight in the larger story of Batman that it becomes incredibly difficult to compact his entire story into one lifetime. Nevermind the idea that he had a nearly impossible situation; He was the guardian of a young boy who was clearly going insane after the death of his parents, but was also his SERVANT. Given the limitations on him, he clearly did the absolute best that could be expected of him, helping forge that angry boy into something approximating a force for good.
Still, Alfred needs to have had enough experience in the British special forces as a field medic to be able to operate as Bruce's surgeon, spent enough time on the London Stage to be considered an accomplished actor, AND have spent enough time with the Waynes that they would choose him as the guardian of their son. Add the fact that our version of Batman is in his late thirties, just how old does Alfred have to be?
The solution we came up with was to make Alfred's family servants of the Wayne family. This allowed Alfred to grow up alongside Thomas Wayne, creating a bond from their childhood. There are elements of this in Alfred's story; In his pre-crisis incarnation he arrived at Wayne Manor once Bruce was already Batman explaining that his family were hereditary servants to the Wayne family. From there, it was simply a matter of working out the elements of his backstory so that they are all given the proper amount of room to make sense.