The Brit Milah or ritual circumcision is celebrated on the eighth day of life of a newborn Jewish male child. It was first performed by Abraham (when he was 99 years old, yikes!) as a sign of his covenant with G-d. The meaning and significance of the ritual is of profound significance, much too complicated for me to engage with here. Much more information can be found here. But it's a joyous occasion, except for the baby, with much celebrating.
The father preparing to put on tefillin before the ceremony.
Grandfather (on the right) and great-grandfather (on the left).
The child and uncle before the ceremony;
Father and son before the ceremony.
Grandfather holding the child while the mohel (a rabbi with surgical training) performs the procedure.