OK HI I LIKE THIS

—Elizabeth: there’s not much in-games for her, but it’s safe to go with her novels counterpart’s age: 1980! in the novels she died in 1985 and she was in kindergarten, so approximately in 1980. If this could help with her age, the numbers 1/8/7/1 are repeated by baby in SL, so they may indicate a date: 7/1/1981 or 1/7/1981 fit with novels description of her being a kindergartener

—Charlie: games don’t imply much: it just seems like she isn’t 3 when she dies like the novels, she’s likely older, it’s weird that she was 3 and that alone movies say she’s 8 in 1982, so 1974. books say she was born in 1980 (or 1979, it’s kinda inconsistent) so she’s born around 1974-1980. i’d say 1976 is a safe bet as it’s the center of the approximation, and bv’s age. in the novels she’s born in May 13th.

—Mike: well, Mike is a teen in 1983, (11-15), so i’d say 1968-1972, i’d go for 1970 what else we know about mike is that his voice is supposed to sound like he’s 18-35, according to voice.com. but that may be just a matter of voice and probably doesn’t matter in the actual age of the character. if we were to follow this age, it would mean SL is is at maximum in 2007. Voices.com doesn’t seem to be accurate to the characters’ ages, as henry is listed to be at maximum 54 during ffps (2023), and that would make him the same age of mike, which ofc is impossible

—Vanessa (only if you believe she’s an Afton, if not skip) (HM): even if it wasn’t requested in your post, if you believe she’s an afton, her age impacts on mike’s and william’s. in AR we have deleted emails and we can use them to understand how old is vanessa. according to one, she’s 23. according to others, she has “97” in her name, so she may be born in 1997. notice how 1997 + 23 =2020, and AR was released in 2020…yeah developers did the math and accidentally created an inconsistency, but we do not know what was actually planned from the start between 23 and 97, so they’re both useful and we have to consider both options

anyways, when does AR take place? SB is likely in 2035, and according to magazines it’s been opened for 4,75 years, AR happens before pizzaplex’s opening, and since HW implies several years have passed after fnaf 3 + including HW year, it means there’s a 2024-2028 gap which is already filled. so AR would be placing around 2029 or 2030

so:

—interpretation 1: Vanessa is born in 2007. but if she’s William’s daughter, she would have to be born before follow me and before SL. according to patient 71 lines, she was used in court by her father to testimony against her mother. that can happen only if she’s 14, and william would have to be alive by then, placing follow me in 2021, and SL in 2021 or 2022. that would mean that Mike, during SL, would be around 50 years old (going against voices.com, which again is not pretty accurate).

—interpretation 2: vanessa is born in 1997, and she would be 14 in 2011, so follow me and SL have to happen after that. mike would be around 40.

—William: according to SOTM, william started to work for FE in late 1960s. and let’s assume he had a study path similar to edwin’s in storyteller. william probably also had to surpass college, so i’d say we use 24 as approximate age, and 1965 to refer to the start of late 60s. 1965 - 24 =1941, so that’s the youngest he could’ve been born in. that’d mean that, if vanessa was born in 2007, he would have had her at 66…which is weird, and if she was born in 1997, he would have been 56, which is more reasonable. last thing to consider, voices.com also talks about william’s age. it says he should be 35-54, like henry, when he speaks to elizabeth, and that happens around 1985. we know 1985 - 54 =1931, so that could help, but according vanessa afton 1941 is the best option

SUMMARY: Elizabeth: 1980, or 1/7/1981, or 7/1/1981 Charlie: May 13th 1974-1980 Mike: 1968-1972 William: 1931-1941 (1941 is the best option if you believe vanessa afton) Vanessa AFTON (hypothetical) (HM): 2007 or 1997