My 24 months son have ankle clonus in both sides since newborn. Mostly this ankle clonus occured less than 5 beats, but several times occured for more than 10 beats (exactly about 11 beats). My son have a good milestone, good development, good posture and no muscle stiffness. He can walk and run normally.
Clonus in my child will appear when I press and push the surface of the sole of his foot strongly

His clonus ussualy appear when asleep and above 1 years old several times his clonus reduced/decreased but then relapsed again.

My son has checked the blood electrolyte components in the laboratory (natrium-kalium-calcium) and the results are all normal

I’ve brought my son to some neuro paediatrics. Some of them said that possible cause of his ankle clonus is immature nervous system (myelin or basal ganglia) and will mature at 2 years old (this clonus also must be totally lost maximum at 2 years old).
But one neuro paediatric said that my child is very normal, no worries, he does not have cerebral palsy. Ankle clonus in children with milestones and good physical is normal, no need for treatment or any examination. Because if there is a nerve disorder then the symptoms are not just clonus only.

The questions:
1. Is it normal for a 2-year-old child without any other health disorder to have ankle clonus?
2. Neuro paediatric that I last visited said that adults also sometimes can have ankle clonus but so far does not interfere with activity and health then it does not need to be treated —> Whether this means there is a possibility that ankle clonus will last a lifetime/forever?
3. Is there a maximum age that ankle clonus must be totally lost?
4. Ankle clonus in my child is unstable, sometimes does not appear but sometimes appears, so does the amount of vibration, sometimes less than 5 beats but sometimes more than 10 beats.
If ankle clonus in a child is still fairly normal whether there is a limit to the amount of vibration?