Stains that won‘t leave

The night before yesterday, I put my baby in my big bed, he wet the bed, I thought that the mattress will not penetrate the mattress, today washing the sheets found that it stained, and also dry on the mattress, girls, what should I do in this situation? Can you get it off?#ask #AskLemon8 #shareyourthoughts#letschat #stain #cleaning #dry #WASH #help