My downstairs shower head drips whenever someone takes a shower in the upstairs bathroom. The downstairs shower is not under the upstairs one. Should I be concerned?

My downstairs shower head drips whenever someone takes a shower in the upstairs bathroom. The downstairs shower is not under the upstairs one. Should I be concerned?
Not a big deal! However I would be curious as to why the sudden change in house pressure when you open a upstairs shower valve would cause a supposedly closed downstairs shower valve to get enough pressure in it to force a column of water up a 1/2" shower raiser 2 feet or more. What's the brand name of the shower valve? How old? One handle or two knobs? Let's here back from you. Regards, Tom

Not a big deal! However I would be curious as to why the sudden change in house pressure when you open a upstairs shower valve would cause a supposedly closed downstairs shower valve to get enough pressure in it to force a column of water up a 1/2" shower raiser 2 feet or more. What's the brand name of the shower valve? how old? One handle or two knobs? Let's here back from you. regards, Tom

Thank you for responding. The shower head is Moen (not sure what the valve is) and both showers have one handle. The house is about 5 years old. I have been here for 3 years. This just started happening about 6 months ago. I notice after using the shower that when I turn on the sink hot water there is pressure built up in the outflow of water for about 2 seconds and then it returns to a normal flow. I was more concerned about this dripping of water from the downstairs shower head when someone upstairs takes a shower. The dripping eventually stops. I hate to have a plumber come out for just occasional dripping water... but I'm hoping there is not a more serious problem somewhere inside the walls. The guy I bought the house from was his own contractor and I'm not sure who did the plumbing. Do you know if general plumbing in a house carries a warranty of more than five years? Thanks for any advice you can give me.