Chapter III of the Prescription Act, 1969 deals with the extinction of debts by prescription. 

But how does this relate to personal injury cases?

Most claims for damages prescribe in three years, but prescription does not run against minors (people under the age of 18), those with severe mental and intellectual disabilities, or those under curatorship.

The Prescription Act affords these creditors at least one additional year after they have reached majority, or the relevant impediment has ceased to exist, to institute a claim.  This means that all minors have at least until at age of 19 years to institute a claim. 

If however the claim arose when the minor was 17 or 18 years old, then that minor will have the usual 3 years to institute the claim. 

Claims by people with incurable, severe and permanent mental or intellectual disabilities will never prescribe.