I do piercing and won't do it til they are 5. Number 1 reason is that ears can grow and are never even, I have had to re pierce lots of ears that were done young and ended up uneven. Number 2 reason at 5 most understand not to pull them, seeing a little toddler with a ripped earlobe is not nice.
I have had lots of mums get angry at me because I won't take their money and do it