The adage you can't teach a dog new tricks is not entirely true. Old dogs can learn just fine, but pups are much more likely to pick up routines naturally.
This post is going to be short and to-the-point.
If we want to teach our children to do the right things, make the right choices, and think the right things, we have to start teaching them when they are young. Even babies can learn that the family prays before eating, for example. Keep baby's plate off her chair until you have finished the prayer. When we have our youngsters follow family routines, they grow up accepting them as part of life.
But as for you, brothers, do not grow weary in doing good.
That doesn't mean that you can never begin new routines with older children; it just might take a little longer for them to stick. But don't give up! Second Thessalonians 3:13 encourages us to not grow weary of doing good. If the new routine is something you feel led to incorporate, keep working at it, even if it seems hard for everyone to remember. Eventually, those routines will become part of your family's daily activities, and you will feel good that your goal was accomplished.