How do I parent a child no longer alive?

“2 KIDS”, I bark at someone who only mentioned I have one. A completely innocent mistake on their behalf, but I am trying to navigate parenting both a living child and one that has died.
Parenting doesn’t stop because they are no longer here. As Dennis’ mother, I have a deep rooted maternal instinct to look after my child; to care for him, bath him, smother him with kisses and cuddles and provide essential love to a happy 5 month old baby. While I know the physical duties of caring for my son whom I will never get to touch again have stopped, the parenting still continues. I have never had to parent a child no longer alive and it’s hard, it is so damn hard. It’s an overwhelming feeling that I must ensure people know he existed, I NEED to make sure he is remembered, I am driven to have him included in everything about our family. My parenting of him these days is a constant battle of how do I do this, or should I do that, how did other parents do it. When writing on birthday or Christmas cards do you include their names too? When taking family photos can you acknowledge that it’s actually a family photo when our baby boy is missing from it? How do you caption a family photo without feeling guilty that he isn’t in it? It makes me feel like a terrible mother, what if he thinks we don’t love him enough to acknowledge him in our photos and new memories created from here on out? I suppose I will scramble finding my feet and what works for our family from here on out, and over the lifetime he will not be with us. For now I always add his initials somewhere special on a birthday or Christmas card and I always tell people we have 2 kids. When talking about my children I tell people about baby Dennis, not to get sympathy but to fill the overwhelming urge I have as a parent to ensure people know he existed and he will not be forgotten.
Parenting any child is never always easy, and parenting a child who is no longer alive doesn’t come with instructions, it comes with immense confusion, silence from others, awkwardness when you talk about your child, broken hearts, broken dreams and more pain then could ever be described. I love both of my children and will continue parenting both of them, my daughter here earth side and my son in the sky.