As the mother of 4 boys, the testicles should descend before birth. The pediatrician always checks when they are born.
Undescended testes exists in 3% of full-term newborn males and in 30% of premature newborn males. Most undescended testes descend spontaneously (ouch!?!) without treatment by age 1.
Funny story about LL cup usage:
Before the games in our league, the umpire always asks the catcher if he has his cup on. Then, to prove it he asks them to tap it, usually by saying, "Show me." Well, this kid was 8 and had not played catcher before, so standing behind home plate, he just reached down in his pants and pulled it out. The umpired almost lost it before he said, "Uhhhh....OK, thanks." The parents were laughing so hard they almost fell out of the stands.