Lighten up Francis; everyone sucks at everything they haven't yet learned how to do well! It's just a matter of practice. Since you said you posted for lighting, I wasn't going to give you a detailed crit, but things to think about:
-They're clearly looking up and at something; what? Having the subject(s) in an image looking at something the viewer of the photo can't see can work, but in this case they both have an excited, happy look, and we want to see why. In short, why aren't they looking at the camera?
-Mom's glasses frames go right through the middle of her eyes.
-Mom has no arms
-Oh... wait she has an arm and it's HUGE!!!!
So.... why not start off with the basics. Set Mom and junior up pretty much as you have them here, but move your shooting position so that they're looking at you. Set your key light up about 35-40 degrees off-axis; probably on the side that junior is on. Set your fill up about 1 1/2 stops below and just off-axis. Raise the key light so that the bottom of the modifier is around middle of Mom's head, and it's angle down at about 30 degrees. Have the fill set to it's more-or-less perpinduclar to the floor and the middle is about the mid-frame.
Now, posing: Have Mom sit upright and look toward the camera, but not stare down the lens. Ensure her glasses are pushed up, necklace sitting properly, rings, watches, etc turned upright. Have junior sitting beside her and leaning on her, but watch out that he doesn't press against her so hard he distorts her flesh. Have Mom put one (or maybe both) arms around him to hug him, but again, not too tightly. Lastly, have junior hug his stuffy so that his arms are occupied.
Et voila...