Yes, but it won't die exept on surface
Your chao will age faster if you spend more time in the Chao Garden with your chao.
No you can not make a chao age faster
It has to be a normal type dark chao or running type dark chao when it evolves make sure you never increase its stats except for in running or stamina.
In 222 CE, Ma Chao died from illness at the age of 47.
"Like most things, Chao can die... A Chao's life usually lasts about 7 - 8 hours on the Dreamcast. On the Gamecube the Chao has an age. When the Chao reaches 5 years old* it will reach the end of its life, and it will cocoon and die after that. But, if your Chao liked you, it will reincarnate and leave an Egg. If it didn't, then sadly your Chao will not reincarnate and will be gone forever. *A Chao Year on the Gamecube lasts around three real life hours. If you care for your Chao extra well, it's years will take longer. Likewise if your Chao is unhappy and get hit alot, it will take shorter to age and in turn, die quicker. Also note, that some studies show that when a Chao breeds with another Chao, its lifespan decreases. The age of your Chao is shown in the Medical Chart with the Chao Doctor (in the Kindergarten)" - Chao Island
Update: so I was using this glitch for infinite animals on sonic adventure 2, and I got my chao's swimming level to 99, but it wasn't old enough to do a second evolution. Can I just keep giving it swimming animals and make it a swim/swim Chao? Or will I have to choose something else?
Yes. Just make it a hero chao through it's entire life (including reincarnations) and then follow the steps to make it a chaos chao
it would be about at level 4, but it all depends on what level stat (A, B, C, D, E) your chao is. To be safe, all chao should be able to swim at level 10
he started swimming at the age of 5
Wait patiently in the chao garden for a very long time make sure you take care of your chao of course after a long time take it to the doctor to check its age it should of gone up if not wait more.
No, on the third lifetime of the chao it must be fed precisely 1 of each type of animal or it will not become a Chaos Chao.
Take your chao to the medical center in the chao kindergarten and see the test results