We have a 2 story home. Flushed upstairs toilet this morning and the downstairs bathtub and shower backed up. I flushed the downstairs toilet and the tub and shower backed up a bit more. I have not tried anything to solve the problem. Thinking the best thing would be to call Roto Rooter but would like to know what the cause is so I know what the long term solution is. Any ideas? Thanks.

Do you have septic tank or are you on sewer system? If you have a septic tank you may need to have your septic tank pumped out.

Most likely a clog in your main drain pipe downstream of all fixtures. Roto Rooter is a good bet unless you own some snakes to rod out a main. Do not open any clean outs before coming back here with more info. Opening a clean out uip stream of the clog could be a real mess.