1
general::
Phrase(s): no wonder
[something is] not surprising. • No wonder the baby is crying. She’s wet. • It’s no wonder that plant died. You watered it too much.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Also, small wonder. It's not at all (or hardly) surprising, as in With the goalie out with a sprained ankle, it's no wonder you lost the game, or If he finished off all of the turkey, small wonder he has a stomachache. [c. A.D. 900]
American Heritage Idioms