Your children badly need to see your faith making your life unpleasant.
You see, real things make demands upon us. A puppy is not the same as a stuffed animal, and even a little child can feel the difference when a play date is cut short to go home and take Fido out for a walk. When my wife was a little girl she had a paper cutout “husband” with whom she played at times, and then at other times she would pack him away in a drawer. That’s not an option with her real husband–I may need to talk, or need dinner, or need a hug, even when she’s tired and out of sorts. Even something as basic as gravity tells us it’s there by restricting what we can do. Real things disrupt your life.
In some parts of the world, Christian children hear their parents telling them God is real by hand-writing copies of the one village Bible, or gathering in hidden rooms to worship, or being carted off to prison or death because they will not deny their Lord. In America, we tell our children God is real by having an Easter egg hunt.