I have a problem between two tenants. The lower tenant tells me the upper tenant's 3 year old runs around too much and wakes them up and interferes with the peace and quiet. A few days ago the lower tenant went up to the upper tenant's door at about 10:30am and banged on it and said to FN keep it down or he would call the police. The lower tenants are home all day because they are unemployed. The upper tenant tells me her daughter was frightened when the lower tenant came up and yelled and banged on their door (daughter was home sick), and she said her daughter is not running around all the time and sometimes runs to the bathroom in the morning and at times likes to dance and run when she is happy as 3 year olds do. Her daughter is gone most of the day in school except when she is home sick. The units have wood floors so more noise gets thru to the lower tenants. This is not the first time the lower tenants complained, yelled and called the police out. The two previous tenants ended up both having a baby and when the baby was starting to walk around the lower tenants went off the handle and said it was like a "living hell" with the baby up and walking. The lower tenant said recently to me I can't believe you rented to a woman with a child after everything we went thru with the previous tenants. I told her I can't discriminated against families with children and nor can you. What to do?