I thought I was going mad to start with but I ran a test over the last 11 hours and some of the pets in my Hatchery don't appear to be aging - their maturity number is remaining the same.

These are the relevant pets:
https://www.sylestia.com/view/pets/?petid=1459561
https://www.sylestia.com/view/pets/?petid=1486423
https://www.sylestia.com/view/pets/?petid=1491705
https://www.sylestia.com/view/pets/?petid=1491819

I checked the maturity of each of my pets at approximately 8.30am this morning and re-checked the maturity at approximately 7.50pm. The results were as follows:

Pet ID - 1459561
Maturity am - 216
Maturity pm - 216

Pet ID - 1486423
Maturity am - 73
Maturity pm - 73

Pet ID - 1491705
Maturity am - 73
Maturity pm - 73

Pet ID - 1491819
Maturity am - 73
Maturity pm - 73

I've also recently manually moved a number of pets from my Hatchery to my Stables and I suspect that the same issue may be occurring with them due to the inconsistencies between their "Age" and "Maturity". These pets are as follows:
https://www.sylestia.com/view/pets/?petid=1437792 (Maturity 216; Age 21)
https://www.sylestia.com/view/pets/?petid=1437888 (Maturity 216; Age 21)
https://www.sylestia.com/view/pets/?petid=1433200 (Maturity 216; Age 22)
https://www.sylestia.com/view/pets/?petid=1444076 (Maturity 216; Age 19)
https://www.sylestia.com/view/pets/?petid=1445346 (Maturity 216; Age 19)
https://www.sylestia.com/view/pets/?petid=1455583 (Maturity 216; Age 16)
https://www.sylestia.com/view/pets/?petid=1455584 (Maturity 216; Age 16)
https://www.sylestia.com/view/pets/?petid=1455582 (Maturity 216; Age 16)
https://www.sylestia.com/view/pets/?petid=1458010 (Maturity 216; Age 16)
https://www.sylestia.com/view/pets/?petid=1467527 (Maturity 216; Age 13)
https://www.sylestia.com/view/pets/?petid=1467528 (Maturity 216; Age 13)

I believe a maturity of 216 is approximately 9 days of age...

I don't know whether that's all of them that are encountering the problem but I'll let you know if I find any more.

Thanks!

I don't think you can see the exact age unless a pet has been tested, IIRC.

Oooohh, that could definitely be why as I haven't tested any of those pets. I'll have to wait and see if Aries will move to the Stables automatically once he reaches adulthood. Thanks!

I could always test some for you and see if that fixes the problem.

ohh, my little featherbutt looks so dashing today *hugs and plops on head*

That would be nice of you. I've set this one up for you to test, if that's still cool. Please feel free to sell back at 1,000g.

Edit: Thanks for testing. You were 100% right, you need to test to get the ongoing maturity updates.

Oh, wow. I did not know that! So if you don't test a pet, it only shows the maturity at the numbers where it changes images. Huh.