Hi anyone can advice LO coming 12 mths paracetamol's dosage? TIA

My LO more then 9kg dosage is still only 3ml by PD.... so I think please get advise from PD...my 3 years old is only 4ml..... eventhough it's paracetamol but got different MG. ..some is 125 some 250 some even is 500...