My son was recently diagnosed with allergies to 5 different types of mold and severe allergies to cats among other things. We live in a rental property and there are cats living in our immediate building and we found a lot of mold in my son's closet. My son was prescribed an epipen. My lease expires July 31st can I leave before due to this problem?

You can't break a lease because your son is allergic to cats but your landlord must remediate the mold. The landlord must be "officially" given notice of the problem and be given adequate time to eliminate the mold. If you walk away from the lease you will be responsible for any lost rent until the unit is re-rented along with any expenses incurred by the landlord. These expenses could include advertising.