BOSTON -- Major Chris Hoffman knew weeks ago that he would have to say goodbye to his family this month, but that didn’t make it any easier.

Hoffman, holding his 3-and-a-half-year-old son on the floor of TD Garden, was struck by the reality of a year-long separation from the toddler.

“I didn’t realize it was going to be that tough,” said Hoffman, whose son was clothed in army fatigues to match his dad's uniform. “It’s really tough.”

About 650 members of the Massachusetts National Guard received an emotional send-off Sunday as they prepared for deployments to Iraq and Afghanistan. Three local military units will begin leaving over the next few weeks.

Members of the 1st Battalion, 101st Field Artillery will team with the Regional Corps Assistance Group to support and mentor Afghan police and army personnel. The National Guard's 164th Transportation Battalion will provide heavy equipment transport services for military operations in Iraq.

It's one of the largest deployments of New England troops since President Barack Obama announced plans to send 30,000 more troops to Afghanistan.

Family members, who filled the arena with signs of love and support, said the difficulty of a year-long separation was hitting home for them at the ceremony as well.

"We’re a family, so we’ll stick through it,” said Jen Curtin, whose husband is heading to Afghanistan. "We love each other.”

Like Hoffman, Sgt. Marilyn Gonzales will leave behind a young child when she ships out to Iraq this month. She said the upcoming year may be easier to bear because her 19-year-old daughter is being deployed with her in the same unit.

“It's hard,” said Gonzales. “Especially leaving a 2-and-a-half-year-old behind, but I'm taking one with me, if that helps with anything.”

For Josephine Giuffre, however, the pain of separation will be doubled. Her two sons will both leave for the Middle East this month.

"They have to do it,” said Giuffre. “It's something that has to be done. God bless them."