It happens.

https://en.wikipedia.org/wiki/Ovotesticular_syndrome

Ovotesticular syndrome (also known as ovotesticular disorder or OT-DSD) is a rare congenital condition where an individual is born with both ovarian and testicular tissue. It is one of the rarest disorders of sex development (DSDs), with only 500 reported cases. Commonly, one or both gonads is an ovotestis containing both types of tissue. Although it is similar in some ways to mixed gonadal dysgenesis, the conditions can be distinguished histologically.

Physical symptoms:

• Enlargement of one or both breasts in men (gynecomastia) (present in 75% of cases)
• Small phallus midway in size between a clitoris and a penis
• Incompletely closed urogenital opening (shallow vagina)
• Abnormal urethra opening on the perineum