More than 1.3 million members of the United States’ armed forces have given their lives defending our country. In Arlington National Cemetery alone, more than 400,000 have been buried since the 1860s.

Memorial Day, which occurs Monday, May 30 this year, is a chance to remember those who have given the ultimate sacrifice while defending this country.

It can be easy to get caught up in our own lives sometimes and forget the meaning of the holiday — for many it is the start of pool season, a day off work, or simply an excuse to have a barbecue with family and friends. And while it’s okay to relax, it’s also important to remember those who have given us the freedom to do so.

We’ve already talked about the history of the holiday and how it began, and provided tips for grieving the loss of a military family member or friend, so this year we want to focus on the heart of the matter — those who have been lost.

The 13 most recent military deaths, according to the Military Times, are below.

1st Lt. David A. Bauders II

Died May 6, 2016, while serving during Operation Inherent Resolve.

Military Times — 1st Lt. David Bauders, 25, died May 6 at Al Asad Air Base in western Iraq. Bauders was serving with the Washington National Guard’s 176th Engineer Co., which deployed to Kuwait and Iraq in April, Guard spokesman Capt. Joseph Siemandel told USA Today. Bauders was commissioned as an engineer in May 2013 after graduating from the University of Portland. The 176th specializes in construction, Siemandel said.

David is survived by his parents, two sisters, and extended family and friends. His family is requesting donations in David’s honor to the National Law Enforcement Officer’s Memorial Fund.

Special Warfare Operator 1st Class Charles H. Keating IV

Died May 3, 2016, while serving during Operation Inherent Resolve.

Military Times — Special Warfare Operator 1st Class Charles H. Keating IV, 31, of San Diego, California, died May 3 in Tal Usquf, Iraq, of combat-related causes. He was assigned to a West Coast-based Navy SEAL Team. Keating was killed by ISIS gunfire on a quick-response force mission to aid American troops under attack, becoming the third American service member to die fighting the Islamic State group.

Chuck is survived by Brooke Clark, to whom he was engaged to be married; his parents; three siblings; and extended family and friends.

Airman First Class Nathaniel H. McDavitt

Died April 16, 2016, while serving during Operation Inherent Resolve.

Military Times — Airman First Class Nathaniel H. McDavitt, 22, of Glen Burnie, Maryland, died April 15 in Jordan Southwest Asia as a result of injuries sustained after extreme winds caused structural damage to the building in which the airman was working. He was assigned to the 52nd Equipment Maintenance Squadron at Spangdahlem Air Base, Germany.

Nathan is survived by his wife, parents, stepfather, five siblings, in-laws, grandparents, and extended family and friends.

Staff Sgt Louis F. Cardin

Died March 19, 2016, while serving during Operation Iraqi Freedom.

Military Times — Staff Sgt. Louis F. Cardin, a 27-year-old field artilleryman with Battalion Landing Team, 2nd Battalion, 6th Marines, was killed when Islamic State group militants launched a rocket attack on a coalition base in Makhmur. Eight other Marines were injured in the attack on the newly established base, which is roughly 60 miles outside of Mosul. Cardin was deployed with the 26th Marine Expeditionary Unit, which sent a detachment of Marines to Makhmur to guard the base. The Marines were supporting Operation Inherent Resolve, the U.S. military’s campaign against ISIS.

Louie is survived by his parents, siblings, and extended family and friends. Funds can be donated in support of constructing a permanent memorial in Temecula, California, his hometown, to honor Louie and other fallen heroes of Temecula.

Sgt. Joseph F. Stifter

Died January 28, 2016, while serving during Operation Inherent Resolve.

Military Times — Sgt. Joseph F. Stifter, 30, of Glendale, California, died January 28 at Al Asad Airbase, Al Anbar Province, Iraq, from wounds suffered when his armored HMMWV was involved in a roll-over accident. Stifter was assigned to the 1st Battalion, 7th Field Artillery Regiment, 2nd Brigade Combat Team, 1st Infantry Division, Fort Riley, Kansas.

Joseph is survived by his wife, two-year-old daughter, parents, siblings, and extended family and friends. His family is requesting donations in Joseph’s honor to the U.S.O.

Maj John D. Gerrie

Died January 22, 2016, while serving during Operation Inherent Resolve.

Military Times — Maj. John D. Gerrie, 42, of Nickerson, Kansas, died January 16 in Al Udeid Air Base, Qatar, from a non-combat related incident. He was assigned to 453rd Electronic Warfare Squadron, Joint Base San Antonio-Lackland, Texas.

John is survived by his wife, three children, mother, siblings, and extended family and friends.

Army Staff Sgt. Matthew Q. McClintock

Died January 5, 2016, while serving during Operation Freedom’s Sentinel.

Military Times — Army Staff Sgt. Matthew Q. McClintock, 30, of Albuquerque, New Mexico, died January 5 in Marjah District, Afghanistan, from wounds suffered when the enemy attacked his unit with small-arms fire. He was assigned to the 1st Battalion, 19th Special Forces Group (Airborne), Washington National Guard, Buckley, Washington.

Matthew is survived by his wife, son, parents, brother, grandparents, and extended family and friends.

Air Force Staff Sgt. Louis M. Bonacasa

Died December 21, 2015, while serving during Operation Freedom’s Sentinel.

Military Times — Air Force Staff Sgt. Louis M. Bonacasa, 31, of Coram, New York, died December 21 near Bagram Air Base, Afghanistan, when his patrol was attacked by a suicide bomber on a motorcycle. He was assigned to the 105th Security Forces Sq, Stewart Air National Guard Base, New York.

Louis is survived by his wife, five-year-old daughter, mother, siblings, and extended family and friends.

Air Force Staff Sgt. Michael A. Cinco

Died December 21, 2015, while serving during Operation Freedom’s Sentinel.

Military Times — Air Force Staff Sgt. Michael A. Cinco, 28, of Mercedes, Texas, died December 21 near Bagram Air Base, Afghanistan, when his patrol was attacked by a suicide bomber on a motorcycle. He was assigned to the Air Force Office of Special Investigations, 11th Field Investigations Sq, Joint Base San Antonio-Randolph, Texas.

Michael is survived by his wife, parents, siblings, and extended family and friends. His family is requesting donations in Michael’s honor to the Wounded Warrior Project.

Air Force Technical Sgt. Joseph G. Lemm

Died December 21, 2015, while serving during Operation Freedom’s Sentinel.

Military Times — Air Force Technical Sgt. Joseph G. Lemm, 45, of Bronx, New York, died December 21 near Bagram Air Base, Afghanistan, when his patrol was attacked by a suicide bomber on a motorcycle. He was assigned to the 105th Security Forces Sq, Stewart Air National Guard Base, New York.

Joseph is survived by his wife, two children, and extended family and friends.

Air Force Staff Sgt. Chester J. McBride

Died December 21, 2015, while serving during Operation Freedom’s Sentinel.

Military Times — Air Force Staff Sgt. Chester J. McBride, 30, of Statesboro, Georgia, died December 21 near Bagram Air Base, Afghanistan, when his patrol was attacked by a suicide bomber on a motorcycle. He was assigned to the Air Force Office of Special Investigations, Detachment 405, Maxwell Air Force Base, Alabama.

Chester is survived by his parents and extended family and friends.

Air Force Staff Sgt. Peter W. Taub

Died December 21, 2015, while serving during Operation Freedom’s Sentinel.

Military Times — Air Force Staff Sgt. Peter W. Taub, 28, of Philadelphia, Pennsylvania; died December 21 near Bagram Air Base, Afghanistan, when his patrol was attacked by a suicide bomber on a motorcycle. He was assigned to the Air Force Office of Special Investigations, Detachment 816, Ellsworth Air Force Base, South Dakota.

Pete is survived by his wife, who is expecting their second child in June; three-year-old daughter, parents, brother, and extended family and friends.

Air Force Maj. Adrianna M. Vorderbruggen

Died December 21, 2015, while serving during Operation Freedom’s Sentinel.

Military Times — Air Force Maj. Adrianna M. Vorderbruggen, 36, of Plymouth, Minnesota, died December 21 near Bagram Air Base, Afghanistan, when her patrol was attacked by a suicide bomber on a motorcycle. She was assigned to the Air Force Office of Special Investigations, 9th Field Investigations Sq, Eglin Air Force Base, Florida.

Adrianna is survived by her wife, son, father, brothers, and extended family and friends.

Bonacasa, Cinco, Lemm, McBride, Taub, and Vorderbruggen all were killed in the same suicide bombing near Bagram Air Base on December 21, 2015.

These are just some of the many servicemen and women that have given their lives. Just in the War on Terror, which began in 2001, more than 6,700 have died and more than 50,000 have been wounded.

As you celebrate your day off or a relaxing day by the pool, don’t forget to think about these men and women who made that possible for you.