Suffolk police are giving advice after officers responded to 11 calls for help involving backyard pools in the last two months, including two fatal drownings involving little kids in just the last week.

Nassau police have responded to 13 calls for help since Memorial Day.

"Make sure kids are trained in basic water safety," said Gerard Hardy, chief of patrol of the Suffolk Police Department. "It's the very young and it's the elderly that are involved in these incidents. Kids 1 to 4 years old, it's the leading cause of death in the United States."

UrSwim swim school founder Marina Mentzel says adult supervision is needed at all times at a pool — whether it's just a day at home or a party. "Drowning can happen quickly and it can happen silently," Mentzel said. "Designate one to two people where their only task is watching the pool. When there's a lot of eyes watching the pool, assume no one is watching the pool and no one is watching your child."

For big parties, hiring a private lifeguard can save lives. "That takes the responsibility off the parents who have 25 different things going on," Hardy said.

Swim instructors say even with a lifeguard, the more eyes on the water, the better. "If you have a group of pre-k kids that have very little or limited experience in the water, you want adults in the water, even a lifeguard is not going to be your only source of safety," Mentzel said. Swim instructors say teaching kids the rules in and around the pool can also save lives. "Just as if you would have those conversations about crossing the street," Mentzel said.

Officials also say having protections in your home and around your pool are vital. "Having alarms, both in the pool, in the water and on doors leading into the pool area is critical," Hardy said.