so when the nonprofit make-a-wish foundation told mateo they would grant him one wish, he knew exactly what it would be. hi, david. every day my mailman comes and delivers, like, mail, and i just, like, think i want to just be a delivery man. reporter: he s ready. i would like to deliver packages to the mail and drive my little u.p.s. truck. my very, very own. reporter: and so mateo partnering up with u.p.s. driver dave cundari. you ready to see your new truck? reporter: opening his truck. whoo! reporter: unloading mateo s very own mini u.p.s. truck. the driving test. he passes. good job, mateo. reporter: loading up deliveries for mateo s mother and grandmother debbie at macy s. hello, david. reporter: his mentor dave, on the job 37 years. being an essential worker