The material is not what I expect

I bought 2 pair s/s bodysuit & legings (sweatpea & you are my sunshine) 6-12mos,when I receive the package after waiting one week of shipping I can not wait to put the dress on my baby,only after one day the fabric is loosing at the leg,and so as the bodysuit the sewing did not do a good job for this product and the material is not stay in the same shape after one wash.