Below is the reply I received from Melb dermatology regarding our problem.
So guess we have finally short listed the products that should help us.
The product recommended Skinceuticals Antioxidant Lip Repair contains Silymarin & Vitamin-E and cost Aust. $68.


Abt the product:- This powerful new treatment helps prevent premature aging of the lips - while restoring moisture and smoothing the surface of the lips. Antioxidant Lip Repair contains two powerful antioxidants, Silymarin and Vitamin-E, to shield the delicate lip area from the ravages of the sun, smoke and air pollution. Special botanical emollients hydrate and heal while an AHA-free exfoliating complex evens and smooths deep lip lines.


Their Reply below:-

You could try a more protective product such as Skinceuticals Antioxidant Lip Repair:

http://www.treatment-skincare.com/Skinceuticals/Correctives/Lip-Repair.html


and reapply it every four hours for several weeks.

Further tests and consultation with a dermatologist are also recommended.