JACKSONVILLE, Fla. -

It can happen in an instant, but the pain lasts a lifetime.

Three children were shot dead over the weekend playing with guns.

The latest shooting happened Saturday in Philadelphia.

Police said a two-year-old boy shot and killed his 11-year-old sister while they were playing with a gun.

Jamara Stevens was fatally shot by a gun police believe was brought into the home by the mother's boyfriend a few hours earlier.

This is the third accidental shooting involving a child since Friday.

The first happened in Waycross when deputies say Taylor Jowers asked a young family member to hold a shotgun and it went off.

Then, a boy from Jacksonville, Montrez Burroughs, was shot and killed in Savannah after picking up a gun while playing with his 12-year-old nephew.

Gun safety experts said there are several things parents can do to prevent these tragic incidents.

Phillip Gazalah with Green Acres Sporting Goods said these tragedies happen way too often...and says they can be avoided if parents lock up when kids are around.

"There's so many devices and it doesn't take much money. You can buy a five dollar gun lock or something a little more advanced."

Advanced like the micro vault, a gun safe which bolts to the bedside stand.

"It has a braille code, finger code that's electronic that you can type the code in."

Or parents can keep it simple with a more basic safe you can keep in your house.

They range in size, going from small to life size.

Gazalah said no gun owner should go without a basic gun lock.

He said they're cheap in price, but worth their weight in gold.

"That's why the rest of this month, we're going to be giving away free gun locks to every customer coming in looking for them." 

Gazalah parents also should think about keeping their locked guns up high so they're out of reach.

"If a kid is curious about an item, there's probably a good chance that they're going to do what you don't want them to do. So if you educate them, you have a better chance of them respecting the firearm and not fearing it."

Gazalah said he's giving out free gun locks in April while supplies last, no purchase necessary.