Warning: the following story is pretty much guaranteed to make you cry.
In October, Ashlee Hammac suffered a parent's worst nightmare when her five-day old son, Ryan, died of a brain dysfunction known as Hypoxic-Ischemic Encephlopathy.
To help her other son, three-year old Tucker, remember his brother and pay tribute to him, Ashlee constructed a sandbox directly next to Ryan's grave.
A photo of Tucker playing alongside his late sibling's tombstone has gone viral on Facebook.
"The more I thought about it, the more I wanted something my other son Tucker could be incorporated in," Hammac told People. "He always goes out there with me, and sits out there, and sings lullabies, and talks to him just like he was there.
"So I wanted it to be special for him too. His favorite thing right now is trucks."
Hammac says Tucker often ass if he can go to "baby Ryan's sandbox."
In the months since Ryan's death, Hammac has worked to keep her son's spirit alive via Pages to Memories, a nonprofit that donates books and blankets to NICUs so families can connect with their sick kids.
"I wanted to help. I wanted other people, because I know it wasn't just me, to have someone to talk to…to have a place they could depend on," Hammac says. "And I wanted to feel like Ryan was helping still, because in those five days he changed our family so much."
Ashlee and her husband also donated Ryan's healthy heart to save the life of another baby and Hammac hopes to meet the other mom someday.