But three year old does, so you are okay with 2 year old.
Just kidding dude, is this a joke, what you think a two year old would do so he/she need a fingerprint background check?
may be cic doctors knows that an under 2 year old child is more susciptable to allergic menifestations and may develop contact dermatitis on fingers due to hyper allergenic formula of the ink. So this may be the reason that the will not involve the infant in pcc.
Correct, it is not a requirement in all countries because all countries do not keep criminal data through fingerprints, they don't have resources or not that advanced. So if you need a PCC from such country, you won't need fingerprinting.
The letter I recieved from CIC along with my stamped passports states the following -
Dear Applicant,
Your visa is now affixed in your passport. If you have accompanying dependents, their visas are also affixed in their respective passports. If your children do not have passports, but are listed in your passport or your spouse's passport, their visa is affixed into that passport.
So obviously as per CIC it is not necessary for minors to have their independent passports. But by law in many countries minors must have their independent passports and cannot be added into their parent passport.