1.5 years child able to sit after 6 months effort by physiotherapy sessions

1.5 years child came at our imchf physiotherapy opd on 10 nov 2022 with delayed milestone.
Muscle tone = flacid
Muscle power = 2/5
Reflexes = 1+

He was not able to sit independently after 5 months of physiotherapy sessions he started sitting indendently for 1-2 mints… With continous physiotherapy sessions for 6-8 month he is now able to sit for 2-5 mints without any support.