Is it possible for mice(rodents) to travel in small bags?

i saw mice for the first time at my dads 2 weeks ago. and he said he killed one. i havent seen any since then. my dad lives in the city. I visited my mom at her house which i had been living for 4 years, last weekend. now today she calls me and says she saw a grey mouse run across the floor and that i had brought it over there.. i have never seen any mouse over there since i had been living there, only rabbits chipmunks groundhogs and squirrels. Is this really possible? She also blames me for bringing roaches over there. is this really possible? if so, how can i get rid of the mouse over at my moms? shes terrified and cant sleep knowing theres a mouse in her house.. im scared of them too.