4 lines, 2 in market

We want to open a USC account where we have 4 lines. 2 will be home in a USC market and get used quite a bit, 2 will be sent to our niece and nephew in Houston. They have usage but not extreme usage. Will USC get upset and cancel all 4 lines even tho only 2 are roaming? Or will heavy usage on the two in market lines make up for the two roaming lines and we might be ok?