Using a small lamp on a timer was helpful when my grandson was still too young to read a clock. It took a few mornings of reminding him, but he got it that he wasn't supposed to get up or call for his parents until the lamp turned on.
That's not the same thing as getting a child to fall back asleep. Toddlers and older generally wake when they can't sleep any more. But you can still culture the understanding that sleep is healthy, and Mommy and Daddy need sleep so they can do everything they need to do. And the child can be permitted a small bedside lamp and a couple of chosen books or toys with which to entertain themselves quietly until the "wake up" light turns on.
A significant problem I see with some of these specially-designed lamps is that they lean heavily into the blue end of the light spectrum. Blue and green light frequencies have been proven to interfere with sleep in many people. Other colors can, too, but the effect is diminished. But blue/green light enters they eye through the eyelid, and stimulates the brain to stop producing melatonin, the sleep-inducing hormone. If you're going to use a night light, it's best kept in the yellow, orange, red or pink range.
Also, since any lamp with a dim bulb can be put on an inexpensive timer, why buy a goofy, plastic, throw-away product?
Good luck with those early-morning z's!