Is it possible for a 3 month old to be teething?

It’s possible

Yes mine is 7 months n has been teething since he was 3 month

Lol, our daughter started teething at 1 month old and had all her teeth at 12 month's

Yes my cousin got her first tooth at 3 months. She had all of her teeth by 12 months.

My son cut his first tooth before four months as well.

My son started at 3 months and from 5 1/2 to 8 1/2 months has 8 teeth!!