Can I parallel a 36v 8ah battery with a 36v 14ah battery on my electric scooter?

I have successfully added an extra 36v 8ah battery to my xiaomi electric scooter but now want to upgrade to a 14ah battery. Or 12ah? if 14ah not possible.. I just don’t know if it’s ok to add a battery with different amp hours? In short; Original scooter battery is 36v 8ah and I want to add an additional 36v 14ah battery to it. Is this possible? I’d just take off the extra battery I have now and connect the 14ah battery right? No additional steps? But that’s a different question