I have recently bought a converted flat that used to be a house (converted about 10 years ago). I own half a garden. Unfortunately it is the bottom half which is under some very large trees. Last year I completely ripped evrtyhting out and laid new turf. It took well and was great in the summer. The problem is that over the autumn and winter all the leaves have fallen onto the grass. I thought I would leave clearing them until they all fell down. I have now cleared them away but most of the grass has died. what sahll I do? Returf over the top or try a hardier grass seed. I am also worried because I have 2 cats that seem to eat everything. Will seed and grass food etc be bad for them?