They are twins

A woman has twins, and gives them up for adoption.

One of them goes to a family in Egypt and is named "Amal."

The other goes to a family in Spain; they name him "Juan."

Years later, Juan sends a picture of himself to his mom. Upon receiving the picture, she tells her husband that she wishes she also had a picture of Amal.

Her husband responds, "But they are twins - if you've seen Juan, you've seen Amal.