A great way to get some exercise is to find something the family can enjoy together, that way you're not spending time away from them and you're all enjoying keeping fit together.
My son and I train and practice Choi Kwang Do, a Korean martial art based on the foudations of Taekwon Do. It enables to do something together, encourage each others progress and practice and train together. It strengthens our bond and provides something in common.
It's different to other sports. I've been playing football far longer than he simply because of my older years. I'm therefore more of a coach than a fellow student.
Because our martial arts are new to both of us are learning together and that's a great thing to share.
Many martial art schools provide family classes allowing mum, dad and the kids to all learn and practice together, but even that isn't the case learning something new all at the same time is a great family activity.
Of course it doesn't have to be martial arts, that's just our thing. It could be tennis, golf, table tennis anything that requires technique, skill and patience.
But if it has a Childrens' Promise that includes something like number 2 on the list in the photo, you might find that useful.