This is a basic XML tuning mod to change the default lifespan in sims' aging. It works with Update 126.96.36.1990 (Cats & Dogs - 15th November 2017).
Since the 1.36 update, the option for having custom age multipliers is gone (as far as I can tell). This means that the "Short" lifespan HAS to be exactly half as long as the "Normal" lifespan, and the "Long" lifespan HAS to be exactly four times. So the updated lifespans are: 112
days (previously 79 days) for "Short", 224
(previously 237) days for "Normal", and 896
(previously 474) days for "Long".
Detailed lifespan for each life stage:
Old versions of the mod, named:-
Old 79-237-474 Aging Mod (only works WITHOUT the Cats & Dogs update, but WITH the Toddlers update)
Old 73-219-438 Aging Mod (only works WITHOUT even the Toddlers update)
are also attached in the 'Files' section.
As of 3rd December 2017, this mod (all aging mods, actually) is conflicting with the latest MC Command Center "hotfix" version 3.9.6. The default EA lifespans are used while using this mod along with MC Command Center 3.9.6.