Mouse in my car, U MUST DIE!

So a few weeks back I went to get the double stroller out of my trunk and noticed mouse droppings on a sweatshirt I had back there. I cautiously picked up the sweatshirt to find huge holes chewed in it. I freaked.... a mouse! I took out the stroller saying out loud "if you ate this stroller your dead meat"... thankfully he didn't chew on it at all but I failed to mention to him that he is still dead meat. We set a trap in my car and trunk for weeks and still no mouse. I vacuumed my entire car hoping that I wouldn't see any more droppings and I have not... HOWEVER, on Monday on the way to drop the kids off at moms Owen says "mamma, mouse, catch it........ WHAT!!!!!! You have to be kidding me...... I immediately pull over look in the back seat and ask him where as calmly as I possibly can and he points to his SHOULDER! OMG, no, no way... I get out open his door and start searching for this mouse that he claims he saw and wanted me to catch. Its no where to be found. Its dark when we leave in the morning so I am convinced that this mouse he saw was close enough for him to see. We have not talked about mice in my car with him so I really feel like he saw this mouse. Now I am so paranoid driving that I will see it or that it will climb up my leg... It has to die.... I have had a trap in my car for over 3 weeks and have no mouse............. I am at my whits end with this thing. I have no droppings anywhere so I don't understand, and Eric went to look under my seats to put my mind at some ease and he found a bag of sausage bites that were untouched/unopened that must have fallen out of my grocery bag a few weeks ago. Wouldn't he have ate through the bag and ate some since he has to be starving????