My son is 12 month old but no teething yet, pls suggest is this normal?

yes its completely normal. dont worry.. keep continue breastfeeding and give healthy foods regularly.

My daughter had her first tooth after one year.... Nothing to worry..

Yeah.. It's normal.. My girl is having only 2 tooth.. 13th month is running now for her

My son had his first teeth at 14 months very normal. Generally the last time frame is 18months . He will get in few weeks