Thanks!!
His breeder was feeding him Whiskas in Jelly and Royal Canin Babycat... we couldn't find the Royal Canin Babycat, so we bought another recommended food, James Wellbeloved Kitten.
My mother in-law did bring around some other brand of food, we did give this to him
My partner and I were speaking about that last night and have decided to keep him on the food we have (Whiskas in Jelly and James Wellbeloved Kitten) and see how it goes.