Thanks everyone for your input!
I never knew a toddler is from age 1-3. I thought a toddler is from age 2-5.
My nephew usually just touches his wee wee when he's naked, as in the bath or right afterwards when he hasn't worn any clothes yet. But as soon as his pants are on, he doesn't really reach for it. He wasn't doing it in public so that wasn't a concern for me. I will keep in mind what y'all said so in case it starts becoming an issue.