Beautiful pets! ^^ Lyio is quite valuable now too. Not sure if you were around at the time but Kioka, Omni and Liyure are now retired(ish), meaning that the only way to obtain them besides buying from other users is through a special egg promotion that usually happens around Christmas.
Of course it's okay to ask questions, that's what I'm here for :D
When removed from your showroom, your pets will continue to age from where they were when put into the showroom. They turn a day older each reset, becoming adolescent at 15 and adult at 30.
So if you bring out a pet that's aged 14, at reset it will turn 15 and become an adolescent. If you bring out a pet aged 40, it will already be adult but will continue to age each day. Birthdays don't affect the aging process ^^
Hope this cleared it up. If you have any other questions don't be afraid to ask :3